TY - JOUR
A1 - Bekemeier, Simon
A1 - Caldeira Rêgo, C. R.
A1 - Mai, H. L.
A1 - Sikia, Ujjal
A1 - Waseda, O.
A1 - Apel, M.
A1 - Arendt, F.
A1 - Aschemann, A.
A1 - Bayerlein, Bernd
A1 - Courant, R.
A1 - Dziwis, G.
A1 - Fuchs, F.
A1 - Giese, U.
A1 - Junghanns, K.
A1 - Kamal, M.
A1 - Koschmieder, L.
A1 - Leineweber, S.
A1 - Luger, M.
A1 - Lukas, M.
A1 - Maas, J.
A1 - Mertens, J.
A1 - Mieller, Björn
A1 - Overmeyer, L.
A1 - Pirch, N.
A1 - Reimann, J.
A1 - Schröck, S.
A1 - Schulze, P.
A1 - Schuster, J.
A1 - Seidel, A.
A1 - Shchyglo, O.
A1 - Sierka, M.
A1 - Silze, F.
A1 - Stier, S.
A1 - Tegeler, M.
A1 - Unger, Jörg F.
A1 - Weber, M.
A1 - Hickel, Tilmann
A1 - Schaarschmidt, J.
T1 - Advancing Digital Transformation in Material Science: The Role of Workflows Within the MaterialDigital Initiative
N2 - The MaterialDigital initiative represents a major driver toward the digitalization of material science. Next to providing a prototypical infrastructure required for building a shared data space and working on semantic interoperability of data, a core focus area of the Platform MaterialDigital (PMD) is the utilization of workflows to encapsulate data processing and simulation steps in accordance with findable, accessible, interoperable, and reusable principles. In collaboration with the funded projects of the initiative, the workflow working group strives to establish shared standards, enhancing the interoperability and reusability of scientific data processing steps. Central to this effort is the Workflow Store, a pivotal tool for disseminating workflows with the community, facilitating the exchange and replication of scientific methodologies. This article discusses the inherent challenges of adapting workflow concepts, providing the perspective on developing and using workflows in the respective domain of the various funded projects. Additionally, it introduces the Workflow Store’s role within the initiative and outlines a future roadmap for the PMD workflow group, aiming to further refine and expand the role of scientific workflows as a means to advance digital transformation and foster collaborative research within material science.
KW - Digitalisation
KW - FAIR principles
KW - MaterialDigital
KW - Scientific workflows
KW - Semantic interoperability
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624088
DO - https://doi.org/10.1002/adem.202402149
SN - 1527-2648
IS - 2402149
SP - 1
EP - 25
PB - Wiley-VCH GmbH
AN - OPUS4-62408
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chen, Yu
A1 - Bo, Zhen-Xing
A1 - Zhou, Hong Bo
A1 - Sun, Bao-An
A1 - Sun, Yong Hao
A1 - Maaß, Robert
A1 - Wang, Wei Hua
T1 - Nanoindentation reveals universal scaling of pop-in plasticity in metallic glasses
N2 - Plastic flow of metallic glasses proceeds intermittently in the inhomogeneous deformation regime. Mediated via shear bands, quasi-static straining gives rise to plastic instabilities that are measured as abrupt displacement bursts or pop-ins. The latter is a well-known feature in nanoindentation, where its first occurrence probes the critical and site-specific stress of nano-scale incipient shear deformation. Here we show that the statistical distribution of the stress and magnitude of the first shear instability, as well as its successive higher-order events, universally follow Weibull statistics across ten different metallic glasses. This indicates a fundamentally identical plastic process across glass-forming alloys and progressing deformation that is governed by a weakest-link phenomenon. This finding stands in strong contrast to crystalline alloys, where both defect nucleation and defect-structure evolution control shear instabilities and depend on the deformation history.
KW - Metallic glasses
KW - Nanoindentation
KW - Intermittent flow
KW - Pop-ins
KW - Weibull distribution
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624772
DO - https://doi.org/10.1016/j.scriptamat.2025.116549
VL - 259
SP - 1
EP - 5
PB - Elsevier Inc.
AN - OPUS4-62477
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rashidi, Reza
A1 - Riechers, Birte
A1 - Rosalie, Julian
A1 - Maaß, Robert
T1 - Annealing-dependent elastic microstructure in a Zr-based metallic glass
N2 - In this letter, we demonstrate the robust presence of an elastic microstructure in a Zr-based metallic glass (MG) with a characteristic length-scale of the order of 100 nm. This length scale increases systematically towards the MG surface in differently sized casts, whereas thermal relaxation homogenizes both the internal length-scale gradient and the magnitude of the elastic fluctuations. Strongest changes during relaxation arise in the stiffest parts of the elastic microstructure. These findings indicate that the elastic microstructure emerges due to cooling constraints and may therefore be a microstructural manifestation of the internal residual stresses that arise during MG-solidification.
KW - Metallic glass
KW - Heterogeneity
KW - Elastic microstructure
KW - Nanoindentation
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610962
DO - https://doi.org/10.1016/j.scriptamat.2024.116380
VL - 255
SP - 1
EP - 5
PB - Elsevier B.V.
CY - Amsterdam, Niederlande
AN - OPUS4-61096
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoffmann, M.
A1 - Schubert, Nils
A1 - Günster, Jens
A1 - Stawarczyk, B.
A1 - Zocca, Andrea
T1 - Additive manufacturing of glass-ceramic dental restorations by layerwise slurry deposition (LSD-print)
N2 - This study is dedicated to the additive manufacturing of a feldspar glass-ceramic for dental applications by LSD-print (layerwise slurry deposition) technology, a variation of binder jetting using water-based ceramic slurries as feedstock. This technology was investigated for the manufacturing of single tooth restoration demonstrators with good aesthetic properties, and to compare the additively manufactured material with a commercial reference. Model restorations with > 99 % relative density were processed with a debinding and firing cycle of 45 min, however the whole process chain accounts for up to 30 hours. Significant differences between LSD-printed and reference materials were found for fracture strength, fracture toughness and Martens parameters. Printing orientation affected shrinkage and fracture strength, but not fracture toughness and Martens parameters. Nevertheless, the results suggest that the LSD-print technology processing the developed slurry is a promising option for manufacturing dental restorations meeting class 1a requirements according to DIN EN ISO 6871:2019–01.
KW - Additive Manufacturing
KW - 3D-printing
KW - LSD-print
KW - Dental ceramics
KW - Glass-ceramic
KW - Debinding
KW - Firing
KW - Sinter-crystallization
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624768
DO - https://doi.org/10.1016/j.jeurceramsoc.2025.117235
VL - 45
IS - 7
SP - 1
EP - 13
PB - Elsevier Ltd.
AN - OPUS4-62476
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ginés-Palomares, Juan-Carlos
A1 - Baasch, Julian
A1 - Stapperfend, Simon
A1 - Facchini, Leonardo
A1 - Linke, Stefan
A1 - Stoll, Enrico
A1 - Günster, Jens
T1 - Laser Melting vs. Laser Sintering: Large Area Heat Processing of Lunar South Pole Simulant
N2 - A key component of future lunar missions is the concept of In-Situ Resource Utilization (ISRU), which involves the use of local resources to support human missions and reduce dependence on Earth-based supplies. This paper investigates the thermal processing capability of lunar regolith without the addition of binders, with a focus on large-scale applications for the construction of lunar habitats and infrastructure. The study used a simulant of lunar regolith found on the Schrödinger Basin in the South Pole region. This regolith simulant consists of 20 wt% basalt and 80 wt% anorthosite. Experiments were conducted using a high power CO2 laser to sinter and melt the regolith in a 80 mm diameter laser spot to evaluate the effectiveness of direct large area thermal processing. Results indicated that sintering begins at approximately 1,180 °C and reaches full melt at temperatures above 1,360 °C. Sintering experiments with this material revealed the formation of dense samples up to 11 mm thick, while melting experiments successfully produced larger samples by overlapping molten layers and additive manufacturing up to 50 mm thick. The energy efficiency of the sintering and melting processes was compared. The melting process was about 10 times more energy efficient than sintering in terms of material consolidation, demonstrating the promising potential of laser melting technologies of anorthosite-rich regolith for the production of structural elements.
KW - Additive Manufacturing
KW - Laser melting
KW - ISRU
KW - Moon
KW - Regolith
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639614
DO - https://doi.org/10.1016/j.amf.2025.200226
SN - 2950-4317
VL - 4
IS - 3
SP - 1
EP - 13
PB - Elsevier Ltd.
AN - OPUS4-63961
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ávila Calderón, Luis
A1 - Shakeel, Y.
A1 - Gedsun, A.
A1 - Forti, M.
A1 - Hunke, S.
A1 - Han, Ying
A1 - Hammerschmidt, T.
A1 - Aversa, R.
A1 - Olbricht, Jürgen
A1 - Chmielowski, M.
A1 - Stotzka, R.
A1 - Bitzek, E.
A1 - Hickel, Tilmann
A1 - Skrotzki, Birgit
T1 - Management of reference data in materials science and engineering exemplified for creep data of a single-crystalline Ni-based superalloy
N2 - The identification of process-structure-property relationships of materials inevitably requires the combination of research data from different measurements. Therefore, the concepts related to FAIR (findable, accessible, interoperable, reusable) data handling, increasingly reported in literature, are particularly important in the materials science and engineering domain. However, they have not yet been integrated into a single, overarching methodological framework, particularly for reference data. Here, we introduce such a framework. Our concept covers data generation, documentation, handling, storage, sharing, data search and discovery, retrieval, and usage. Furthermore, we prototypically implement it using a real dataset with creep data of a single-crystal CMSX-6 Ni-based superalloy. The presented implementation is traceable and permanently accessible through open repositories. The individual elements considered in the framework ensure the functionality and usability of the data and, thus, the adherence to the FAIR principles. In conjunction with this, we present a definition for reference data of materials. Our definition underlines particularly the importance of a comprehensive documentation, e.g., on material provenance, data processing procedures, and the software and hardware used, including software-specific input parameters, as these details enable data users or independent parties to assess the quality of the datasets and to reuse and reproduce the results. Reference data that is managed according to the proposed framework can be used to advance knowledge in the materials science and engineering domain, e.g., by identifying new process-structure-property relations.
KW - Referenzdaten
KW - NFDI-MatWerk
KW - Data schema
KW - Research Data Management
KW - Reference Data
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625047
DO - https://doi.org/10.1016/j.actamat.2025.120735
VL - 286
SP - 1
EP - 15
PB - Elsevier Inc.
AN - OPUS4-62504
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zaiser, Erika
A1 - Fareed, Adnan
A1 - Manzoni, Anna Maria
A1 - Paulisch-Rinke, Melanie C.
A1 - Hsu, Wei-Che
A1 - Yeh, An-Chou
A1 - Murakami, Hideyuki
A1 - Vogel, Florian
A1 - Maaß, Robert
T1 - Pinning-dominated strengthening in high-entropy superalloys
N2 - Hierarchical microstructural design of high-entropy superalloys offers novel strengthening pathways beyond classical superalloys. Here we assess the strength of isolated γ’ precipitates with and without an additional internal γ nanophase. The results show that nano-precipitation within the γ’ phase leads to a marked statistical reduction of the dislocation-nucleation limited yield strength. In concert with disorder-driven chemical weakening of the γ’ phase, these findings indicate that bulk strengthening due to hierarchical microstructural design in high entropy superalloys must primarily be pinning dominated.
KW - High-entropy alloys
KW - Superalloys
KW - Dislocation nucleation
KW - Plasticity
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637590
DO - https://doi.org/10.1016/j.scriptamat.2025.116874
SN - 1359-6462
VL - 268
SP - 1
EP - 6
PB - Elsevier Inc.
AN - OPUS4-63759
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ikeda, Yuki
A1 - Han, Seungchang
A1 - Wallis, Theophilus
A1 - Darvishi Kamachali, Reza
A1 - Maaß, Robert
T1 - On the preference of liquid-metal embrittlement along high-angle grain-boundaries in galvanized steels
N2 - Focusing on the early stages of liquid-metal embrittlement (LME) of Zinc (Zn) coated advanced high-strength steels, we show that the Zn infiltration path prior to grain-boundary decohesion and therefore cracking distinctly follows high-angle grain boundaries (HAGBs). This selective transport prior to LME-induced microcracking rationalizes the experimentally observed post-mortem cracking along martensitic HAGBs. We discuss the selective Zn transport and GB-weakening in terms of an misorientation-angle dependent atomic density and diffusivity, and its effect on GB-segregation.
KW - Liquid-metal embrittlement
KW - Advanced high-strength steels
KW - Grain boundaries
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631103
DO - https://doi.org/10.1016/j.scriptamat.2025.116723
SN - 1359-6462
VL - 265
SP - 1
EP - 5
PB - Elsevier Inc.
AN - OPUS4-63110
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Geffroy, P.-M.
A1 - Schubert, Nils Hendrik
A1 - Günster, Jens
A1 - Zocca, Andrea
T1 - Quantification of in-plane stress development during drying of tape-cast ceramic layers by cantilever deflection method
N2 - The control of stress development in cast ceramics during drying is usually one of critical steps in ceramic processes, which is important also for additive manufacturing technologies using a suspension as feedstock. This work introduces a method based on the cantilever deflection method, to simultaneously quantify the kinetics of solvent evaporation, the shrinkage and the intensity of in-plane stresses developed during drying. Particular attention is given here to the experimental limits of the method and to the optimization of the experimental conditions to suitably measure the intensity of in-planar stress in the coating. The optimized method is applied to
four alumina slurries for the water-based additive manufacturing technology LSD-print. Four stages of drying are identified and discussed in relation with the granulometry and morphology of the alumina ceramic particles.
KW - Additive Manufacturing
KW - Tape casting
KW - Ceramic layers
KW - Drying stress
PY - 2025
DO - https://doi.org/10.1016/j.jeurceramsoc.2024.116868
VL - 45
IS - 1
SP - 1
EP - 10
PB - Elsevier B.V.
AN - OPUS4-61044
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Falkenberg, Rainer
A1 - Kamachali, Reza Darvishi
T1 - Segregation-induced hydrogen embrittlement in titanium
N2 - Although titanium offers an optimal combination of strength, low weight, and toughness for various applications, it suffers from a drawback: loss of ductility upon exposure to hydrogen. In this work, we couple CALPHAD-integrated density-based thermodynamic modelling of hydrogen segregation with an experimentally calibrated fracture model to investigate its on crack propagation in titanium. Here we propose to model the crack propagation path as a quasi-interface with slightly opened structure and reduced atomic density, enabling interstitial hydrogen segregation. The atomic density is then directly linked with the damage parameter. We found that hydrogen segregation in titanium undergoes a significant transition such that above a threshold of only few atomic percent hydrogen in the solid solution, the interfacial hydrogen concentration exceeds 20 at.%. Integrating this information into our fracture model, the material damage evolution could be explained by a segregation-affected Griffith crack energy, resulting in material decohesion. We found that the segregation transition and subsequent embrittlement effects are critically sensitive to the temperature in the system. The present results suggest a mechanism underlying the sudden loss of fracture toughness during crack propagation, in relation to the ductile-to-brittle transition observed in titanium alloys exposed to hydrogen. The proposed CALPHAD-integrated chemo-mechanical framework can be further generalised for studying more complex failure mechanisms in various materials.
KW - Segregation transition
KW - Hydrogen embrittlement
KW - Titanium alloys
KW - Crack propagation
KW - Ductile-to-brittle transition
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655451
DO - https://doi.org/10.1016/j.mtla.2025.102411
SN - 2589-1529
VL - 41
SP - 1
EP - 12
PB - Elsevier Inc.
AN - OPUS4-65545
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Günster, Jens
A1 - Wang, Gong
A1 - Tian, Xiaoyong
T1 - 3D Printing Technologies for Extreme Environment in Space
N2 - 3D printing technology can realize the rapid fabrication of complicated structures with short production chain, which just meet the requirements for space manufacturing in the future. However, 3D printing technologies in space are still challenging due to the harsh conditions, such as microgravity, high vacuum, and large temperature difference. Meanwhile, in-situ resource utilization and recycling must be considered as a cost effective and resilient resource for 3D printing in space. On the contrary, extreme environmental conditions such as high vacuum and microgravity can also offer significant advantages for advanced materials with high purity and performance. In-situ fabrication of ultra-large components would overcome the weight and structural limitations imposed by rocket launch and change the future strategy for space exploration. The aim of this specially issue is therefore to provide a platform for discussing the potential technologies for 3D printing in space.
KW - Additive Manufacturing
KW - space
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652654
DO - https://doi.org/10.1016/j.amf.2025.200248
SN - 2950-4317
VL - 4
IS - 3
SP - 1
EP - 2
PB - Elsevier
AN - OPUS4-65265
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chouquet, Xavier
A1 - Bolten, Julia
A1 - Prinz, Carsten
A1 - Günster, Jens
A1 - Zocca, Andrea
ED - Vincenzini, P.
T1 - Direct ink writing of zeolite-like AQSOA Z02 for envisioned applications in solar-driven atmospheric water harvesting: Paste formulation and effect of thermal treatments on the water sorption propertie
N2 - This work presents the development of porous water adsorbent bodies with complex geometries shaped by direct ink writing additive manufacturing. AQSOA FAM Z02 (Z02), a commercial material similar to SAPO-34 with chabazite structure, was selected as sorbent material. Dynamic vapor sorption analysis demonstrated that Z02 adsorbs and desorbs up to 30 % of its own mass in each cycle, highlighting its potential for this application. To optimize its printability for direct ink writing, aqueous pastes composed of Z02 and bentonite were formulated. Bentonite served as the inorganic binder and was responsible for the mechanical stability of the printed porous bodies after heat treatment. The most suitable paste composition was identified and used to fabricate scaffold structures. These structures were then subjected to different heat treatments at 650 °C, 750 °C and 850 °C to find a suitable compromise between mechanical stability and retention of the sorption properties. Scaffold structures printed with a 20 wt% of bentonite binder were mechanically stable (1.9 ± 1.1 MPa compressive strength) and retained a maximum water uptake of ca. 25 wt% after heat treatment at 750 °C for 1 h.
KW - Direct ink writing
KW - Zeolite
KW - Direct ink wriDynamic vapor sorption
KW - Bentonite Water harvesting
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643150
DO - https://doi.org/10.1016/j.ceramint.2025.09.314
SN - 0272-8842
SP - 1
EP - 12
PB - Elsevier Ltd.
AN - OPUS4-64315
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Eisenbart, Miriam
A1 - Hanke, Thomas
A1 - Bauer, Felix
A1 - Beygi Nasrabadi, Hossein
A1 - Junghanns, Kurt
A1 - Dziwis, Gordian
A1 - Tikana, Ladji
A1 - Parvez, Ashak Mahmud
A1 - van den Boogaart, Karl Gerald
A1 - Sajjad, Mohsin
A1 - Friedmann, Valerie
A1 - Preußner, Johannes
A1 - Ramakrishnan, Anantha Narayanan
A1 - Klengel, Sandy
A1 - Meyer, Lars‐Peter
A1 - Martin, Michael
A1 - Klotz, Ulrich Ernst
A1 - Skrotzki, Birgit
A1 - Weber, Matthias
T1 - KupferDigital: Ontology‐Based Digital Representation for the Copper Life Cycle
N2 - The copper life cycle comprises numerous stages from the alloy production to the manufacturing and usage of engineered parts until recycling. At each step, valuable data are generated and stored; some are transferred to the subsequent stations. A thorough understanding of the materials’ behavior during manufacturing processes or throughout their product lifetime is highly dependent on a reliable data transfer. If, for example, a failure occurs during the service life, information about the manufacturing route can be of decisive importance for detecting the root cause of the failure. Additionally, the life cycle assessment hinges on the availability of data. Recording and storing interoperable structured data is, therefore, a thriving research field with huge implications for the economic strength of the manufacturing industry. In the KupferDigital project, it is demonstrated how an ontology‐based data space can be utilized not only as an innovative method for storing and providing interoperable life cycle data but also as a means to enable automated data analysis and evaluation, leading to new insights and the creation of new knowledge using semantic data and technologies. This work illustrates how data recorded at different research facilities can be integrated into one single data space, allowing queries across heterogeneous sources.
KW - Copper Alloy
KW - Ontology
KW - Digitalization
KW - Data Space
KW - Semantic Representation
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630213
SN - 1527-2648
DO - https://doi.org/10.1002/adem.202401735
VL - 27
IS - 8
SP - 1
EP - 29
PB - Wiley
AN - OPUS4-63021
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Waqfi, R. A.
A1 - Khan, C. J.
A1 - Irving, O. J.
A1 - Matthews, Lauren
A1 - Albrecht, T.
T1 - Crowding Effects during DNA Translocation in Nanopipettes
N2 - Quartz nanopipettes are an important emerging class of electric single-molecule sensors for DNA, proteins, their complexes, as well as other biomolecular targets. However, in comparison to other resistive pulse sensors, nanopipettes constitute a highly asymmetric environment and the transport of ions and biopolymers can become strongly directiondependent. For double-stranded DNA, this can include the characteristic translocation time and tertiary structure, but as we show here, nanoconfinement can also unlock capabilities for biophysical and bioanalytical studies at the single-molecule level. To this end, we show how the accumulation of DNA inside the nanochannel leads to crowding effects, and in some cases reversible blocking of DNA entry, and provide a detailed analysis based on a range of different DNA samples and experimental conditions. Moreover, using biotin-functionalized DNA and streptavidinmodified gold nanoparticles as target, we demonstrate in a proof-of-concept study how the crowding effect, and the resulting increased residence time in nanochannel, can be exploited by first injecting the DNA into the nanochannel, followed by incubation with the nanoparticle target and analysis of the complex by reverse translocation. We thereby integrate elements of sample processing and detection into the nanopipette, as an important conceptual advance, and make a case for the wider applicability of this device concept.
KW - DNA translocation
KW - Transport
KW - Resistive-pulse sensing
KW - Nanopores
KW - Nanopipettes
KW - Crowding
KW - Confinement
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630448
DO - https://doi.org/10.1021/acsnano.5c01529
SN - 1936-086X
VL - 19
IS - 17
SP - 1
EP - 9
PB - ACS Publications
AN - OPUS4-63044
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Evans, Alexander
A1 - Schröder, Jakob
A1 - Pirling, T.
A1 - Ulbricht, Alexander
A1 - Suárez Ocaño, Patricia
A1 - Bruno, Giovanni
T1 - Resolving the Subsurface Residual Stress Maximum in Laser Powder Bed-Fused 316L Stainless Steel by Diffraction-Based Analysis
N2 - Laser powder bed fusion (PBF-LB/M) is a metal additive manufacturing process. Due to the complex nature of the layer-wise, repeated heating and cooling cycles, it tends to generate high-magnitude residual stresses. If not correctly understood and mitigated through in- or post-process approaches, these residual stresses can be detrimental as they are often tensile at the surface. However, determining the magnitude and location of peak tensile residual stresses is not trivial as they are often located subsurface. This work focuses on determining the magnitude and location of these deleterious tensile residual stresses in a PBF-LB/316L specimen. Two diffraction-based Methods are used to reveal the relationship between the residual stresses and the underlying microstructure. On the one hand, high spatial resolution Neutron diffraction is used to determine triaxial stresses from the bulk to a depth of 0.15 mm. On the other hand, laboratory X-ray diffraction coupled with electrolytical layer removal allows the biaxial residual stress depth profile to be probed from the surface to a depth of about 0.6 mm. The results show a good agreement between the two methods. The peak residual stress is shown to be 500 MPa, which appears as a plateau between 0.08 and 0.35 mm in depth.
KW - Residual stress
KW - Diffraction
KW - Laser Powder Bed Fusion
KW - 316L
KW - Additive manufacturing
KW - Microstructure
KW - AGIL
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652138
DO - https://doi.org/10.1007/s11837-025-07719-y
SN - 1543-1851
VL - 77
IS - 12
SP - 9726
EP - 9737
PB - Springer Nature
AN - OPUS4-65213
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belli, Renan
A1 - Hartmann, Sabine
A1 - Lubauer, Julia
A1 - Pereira, Raíssa Monteiro
A1 - Hurle, Katrin
A1 - Yin, Ling
A1 - Mieller, Björn
A1 - Lohbauer, Ulrich
T1 - Improving the chipping resistance of pre-sintered zirconia white-bodies
N2 - Objectives: The high occurrence of fractures, cracking and chipping of zirconia pre-sintered blanks and blocks during machining decreases their yield and can transfer lifetime-limiting racks to the final sintered restoration. This study has the objective of characterizing the mechanical and fracture properties of two zirconia compositions while varying temperature and time of pre-sintering, in order to assess the space for possible improvement.
Methods: We selected two typical granular powders with 3 mol% (3YSZ, Zpex®, Tosoh) or 5 mol% (5YSZ, Zpex Smile®, Tosoh) yttria-stabilized zirconia and two pre-sintered commercial analogs (IPS e.max® ZirCAD MO, Ivoclar and Katana™ STML, Kuraray). The debinding and pre-sintering stages of the experimental powders were characterized using thermal analyses (differential scanning calorimetry and thermogravimetry), and the crystal phase composition was quantified using X-ray diffraction (XRD). Physical and mechanical properties such as density, hardness, flexural modulus, biaxial flexural strength and fracture toughness were measured for two pre-sintering temperatures (1000 ◦C, 1100 ◦C) and increasing holding times at those temperatures (2 h, 4 h, 6 h). The chipping resistance for those conditions was quantified using the edge chipping test using a Vickers diamond indenter.
Results: Thermal analyses revealed that both powders show comparable debinding behavior and contained approx. 3.8 mass % organic binder, which burns-out completely between 300 and 400 ◦C. The crystallographic phase changes occurring during the 2–6 h at 1000 ◦C and 1100 ◦C was not detectable in the DSC signal, but quantifiable by XRD. Namely, a major content of monoclinic phase in both powders transforms completely into the two tetragonal phases, starting below 1000 ◦C and concluding above 1100 ◦C. All physical and mechanical properties increased with holding time for both temperatures, though more steeply for pre-sintering at 1100◦C. Edge chipping resistance response was well aligned with other fracture properties, with a more marked improvement for 3YSZ pre-sintered at 1100 ◦C. For all properties, the 3YSZ zirconia showed statistically-higher values for the same temperature-time conditions, in agreement with the values obtained for the commercial materials as well.
Significance: The results demonstrate the weakness of pre-sintered zirconia products concerning fracture properties, but also the potential for improvement as related to type of zirconia and pre-sintering conditions. This study outlines the use of a set of mechanical tests that can characterize chipping resistance and guide future research engaging in optimizing the machining resistance of pre-sintered zirconia products.
KW - Zirconia
KW - Fracture
KW - White body
KW - Dental materials
KW - Pre-sintering
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653457
DO - https://doi.org/10.1016/j.dental.2025.12.012
SN - 0109-5641
SP - 1
EP - 12
PB - Elsevier Inc.
AN - OPUS4-65345
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Singh, Shobhit Pratap
A1 - Löwe, Peter
A1 - Schriever, Sina
A1 - Olbricht, Jürgen
A1 - Rehmer, Birgit
A1 - Nolze, Gert
A1 - Skrotzki, Birgit
T1 - High-throughput creep evaluation of IN738LC in bending using digital image correlation at 850 °C
N2 - High-temperature alloys, when used in structural applications, undergo slow time-dependent deformation known as creep. Assessing creep behavior is critical for estimating the in-service life of these alloys. Conventionally, uniaxial creep tests are widely conducted at elevated temperatures to determine creep rates. In recent years, bending creep of cantilevers, when combined with digital image correlation (DIC), has emerged as a promising high-throughput technique for rapidly estimating creep life. However, the applicability of bending creep above 700 ◦C for high-temperature alloys using DIC has not been fully established. In this work, we compare uniaxial creep rates of the nickel-based superalloy IN738LC with bending creep rates measured at 850 ◦C using high-temperature DIC. The bending creep data show excellent agreement with uniaxial creep results in the stress range of 240–360 MPa. The measured creep xponent, a critical rate-determining parameter, is found to be ~8 for both uniaxial and bending creep, with the rate data scattered within a factor of two. An in-house experimental setup was developed to perform bending creep tests at high temperatures, with strain monitored through DIC. Our results demonstrate that bending creep, combined with DIC, provides a reliable and efficient method for creep testing of high-temperature alloys. Compared to conventional uniaxial creep experiments, this approach requires significantly less time and material, thereby reducing effort, energy, and cost. We anticipate that this technique will serve as a foundation for testing precious high-temperature materials. For instance, in ongoing rapid discoveries of advanced alloys, in-service creep life can be evaluated much faster with reduced material requirements. Moreover, this method holds strong potential for application to high-entropy alloys and additively manufactured alloys designed for demanding high-temperature environments.
KW - Digital image correlation
KW - Bending creep
KW - Nickel-based superalloys
KW - High throughput testing
KW - High-temperature materials
PY - 2025
UR - https://www.sciencedirect.com/science/article/pii/S0921509325017034?via%3Dihub
DO - https://doi.org/10.1016/j.msea.2025.149479
VL - 950
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-64814
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beygi Nasrabadi, Hossein
A1 - Klotz, Ulrich E.
A1 - Tiberto, Dario
A1 - Vafaeenezhad, Hossein
A1 - Mishurova, Tatiana
A1 - Skrotzki, Birgit
T1 - Effect of keyhole and lack-of-fusion pores on the anisotropic microstructure and mechanical properties of PBF-LB/M-produced CuCrZr alloy
N2 - Due to the high reflectance and heat conductivity of copper and its alloys, the processing window for laser-based powder bed fusion (PBF-LB/M) processing of high-density copper components fundamentally overlaps with conduction and keyhole melting zones, resulting in the emergence of certain pores in the structure of printed parts. The present research aims to study how the development of process-induced lack-of-fusion or keyhole porosities during the PBF-LB/M process can affect the anisotropic microstructure and mechanical properties of the produced copper alloys. For this purpose, several samples were produced utilizing a similar CuCrZr-feedstock composition but varied process parameters from different areas of the PBF-LB/M processing window, specifically at laser powers of 300 W and 380 W which define the boarders of the conduction and keyhole regimes. X-ray computed tomography (XCT) revealed that the 300-W and 380-W samples achieved relative densities of 98.88% and 99.99%, respectively, with elongated lack-of-fusion pores forming at 300 W and semi-spherical keyhole pores at 380 W. Microstructural analyses employing scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) demonstrated strong anisotropy in different build directions of the samples, owing to the growth of long columnar grains with intense < 101 orientation along the build directions. Here, the emergence of different types of pores can cause competition between the epitaxial growth of columnar grains and the heterogeneous nucleation of new grains on the layers’ interfaces, thereby significantly varying the grain size, preferred orientation, crystallographic texture, and microstructural anisotropy of the samples. Furthermore, compression tests and nanoindentation measurements of the printed alloys in the longitudinal and transverse directions revealed that the 300 W and 380 W samples exhibited compressive strength anisotropies of 0.061 and 0.072, and average nanoindentation hardness values of 1.3 GPa and 1.5 GPa, respectively. The orientation of elongated lack-of-fusion porosities perpendicular to the loading axis was identified as the most damaging factor, significantly reducing mechanical performance compared to the uniformly distributed keyhole pores.
KW - Copper Alloy
KW - Laser-based powder bed fusion
KW - Microstructure
KW - Mechanical properties
KW - X-ray computed tomography (XCT)
KW - Porosity
KW - Anisotropy
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625655
DO - https://doi.org/10.1007/s40964-025-00972-2
SN - 2363-9520
SP - 1
EP - 15
PB - Springer Science and Business Media LLC
AN - OPUS4-62565
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schröder, Jakob
A1 - Fritsch, Tobias
A1 - Ferrari, Bruno
A1 - Altmann, Mika León
A1 - Bruno, Giovanni
A1 - Toenjes, Anastasiya
T1 - Laser powder bed fusion: Defect type influences critical porosity re-growth during reheating after hot isostatic pressing
N2 - Despite the remarkable product design flexibility offered by additive manufacturing (AM) techniques, such as laser powder bed fusion, AM processes are susceptible to the formation of defects. In this context, the control of process parameters and the application of post-processing treatments, such as hot isostatic pressing (HIP), are of paramount importance to achieve the desired mechanical properties. The present study investigates the effectiveness of HIP as a function of process parameters in laser powder bed fused Ti-6V-4Al (PBF-LB/Ti64) using X-ray computed tomography. The process parameters are modified to obtain reference samples with low porosity, lack of fusion defects, or keyhole porosity. In all instances, subsurface keyhole porosity was observed in the as-built parts. Moreover, it was found that the efficacy of pore closure is dependent on the specific defect type. In the case of low porosity and keyhole pores, HIP resulted in effective closure. Conversely, larger lack of fusion defects were not closed due to their interconnectivity and the entrapment of argon gas. Subsequent heat treatments above the β-transus temperature allowed the investigation of the impact of defect type on porosity re-growth. For the first time, we reveal that lack of fusion defects are affected by considerable pore re-growth during post-HIP heat treatments of PBF-LB/Ti64. Such phenomenon is driven by the increasing internal pore pressure and local creep deformation at high temperatures. In contrast, re-growth is limited in samples with low porosity or keyhole pores.
KW - Additive Manufacturing
KW - Hot Isostatic Pressing
KW - Titanium
KW - Laser Powder Bed Fusion
KW - X-ray Computed Tomography
KW - Heat Treatment
KW - Porosity
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629289
DO - https://doi.org/10.1016/j.jmatprotec.2025.118839
VL - 340
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-62928
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schröder, Jakob
A1 - Han, Ying
A1 - Fritsch, Tobias
A1 - Hejazi, Bardia
A1 - Ulbricht, Alexander
A1 - Skrotzki, Birgit
A1 - Bruno, Giovanni
T1 - X-ray computed tomography quantifies primary phases and reveals crack morphology in high-cycle fatigue of aluminum alloy EN AW-2618A
N2 - Since the introduction of high-strength aluminum alloys understanding their fatigue behavior is of high interest for the structural integrity of engineering components, in this context, the alloy EN AW-2618A gains its high strength from both nanometer size precipitates and micrometer size primary phases. The latter phases are often identified as crack initiation sites. In this study, it uses a combination of synchrotron and laboratory-based X-ray computed tomography to image and quantify such primary phases and the fatigue cracks appearing in interrupted tests. Based on the gray-level differences in the synchrotron X-ray computed tomography scans, this study is able to distinguish low- and high-absorbing particles. The dominant (volume fraction >99%) high absorbing primary phase can be quantified in good agreement with results of Thermo-Calc calculations. To image the fatigue crack, laboratory X-ray computed tomography scans are performed at different tensile loads to open the crack. The results show that with an appropriate crack opening tensile load, the fatigue crack morphology can be reliably revealed. Based on these results, the influence of the primary phases on the fatigue crack initiation and propagation are discussed.
KW - X-ray computed tomography
KW - Fatigue
KW - Aluminum
KW - Primary phases
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632724
DO - https://doi.org/10.1002/adem.202500235
SN - 1527-2648
SP - 1
EP - 9
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-63272
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beygi Narsabadi, Hossein
A1 - Vafaeenezhad, H.
A1 - Klotz, U.E.
A1 - Tiberto, D.
A1 - Hosseinabadi, F.
A1 - Mishurova, Tatiana
A1 - Bruno, Giovanni
A1 - Skrotzki, Birgit
T1 - XCT-assisted micromechanical modeling of the effect of pores on the plastic deformation and mechanical characteristics of PBF-LB/M-produced copper alloys
N2 - Due to the low absorption of fiber laser by copper particles, the laser-based powder bed fusion (PBF-LB/M) processing of copper components is accompanied by the development of different types of porosities within the printed samples. This research aims to assess the consequences of various process-induced pores on the me
chanical characteristics and deformation of PBF-LB/M-produced copper alloys. Several copper alloys were processed using metal-coated particles and varied laser intensities, yielding samples with different types and amounts of porosities. For instance, CuCrZr alloys processed at 325 J/mm³ and 257 J/mm³ had 0.009 % and 1.117 % porosities, dominated by keyhole and lack-of-fusion pores, respectively. Moreover, PBF-LB/M pro cessing of Cr- and Nb-coated CuNi3SiCr particles accompanied by the generation of 0.004 % and 1.861 % porosities within the samples, predominantly featuring metallurgical and oxidation pores, respectively.
Compression and nanoindentation tests revealed that the CuNi3SiCr alloy exhibited superior mechanical properties compared to the CuCrZr sample (nanoindentation hardness values 2.2 GPa and 1.4 GPa, respectively), while the presence of lack-of-fusion pores notably diminished their mechanical performance. X-ray computed tomography (XCT) reconstruction slices and scanning electron microscopy (SEM) images were then used for developing the representative volume elements (RVEs) based micromechanical models. The micromechanical
simulations established a structure-property correlation that can simulate the compressive deformation and mechanical characteristics of PBF-LB/M-produced copper alloys as a function of their incorporated pore characteristics. Due to the closure of the pores at the first stages of deformation, samples with minimal keyhole and metallurgical porosities exhibited homogeneous plastic deformation. On the other side, based on the JohnsonCook model, strain concentration and crack propagation around the lack-of-fusion pores lead to damage initi
ation in the printed samples at a strain level of 5 %
KW - X-ray Computed tomography
KW - Defects
KW - Copper alloys
KW - PBF-LB/M
KW - Micromechanics
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624004
DO - https://doi.org/10.1016/j.msea.2025.147836
SN - 0921-5093
VL - 924
PB - Elsevier B.V.
AN - OPUS4-62400
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Suárez Ocaño, Patricia
A1 - Ávila Calderón, Luis
A1 - Agudo Jácome, Leonardo
A1 - Rehmer, Birgit
A1 - Mohr, Gunther
A1 - Evans, Alexander
A1 - Skrotzki, Birgit
T1 - Effect of 700–900 °C heat treatments and room and high temperature tensile deformation on the microstructure of laser powder bed fused 316L stainless steel
N2 - The effect of post-processing heat treatments on the hierarchical microstructure evolution and mechanical strength of the austenitic stainless steel 316L produced by laser powder bed fusion has been investigated. Heat treatments between 700 and 900 ◦C and 0.5 to 3 h, were applied to samples treated at 450 ◦C for 4 h. The results showed a stable microstructure at all studied temperatures and times in terms of grain size, morphology, aspect ratio, density of low-angle grain boundaries, and texture. However, temperature and time promoted the diffusion of segregated elements together with a reduction in dislocation density and disappearance of the cellular structure. This was associated with a reduction in hardness and tensile proof strength at both room and high temperature. In addition, microstructural characterization coupled with thermodynamic CALPHAD-based equilibrium calculations showed that the formation of carbides and intermetallic phases was already visible after annealing at 800 ◦C for 3 hours, although these intermetallics did not affect the tensile properties at this level. Analysis of the microstructure evolution after tensile deformation showed differences in the deformation mechanisms at room and high temperature, with twinning and martensitic transformation occurring at room temperature, the latter not widely reported for additively manufactured 316L. Finally, comparisons with similar materials produced under comparable conditions showed differences in the tensile properties, attributed to differences in chemical composition and the associated presence of stacking faults in the undeformed state.
KW - Additive manufacturing
KW - 316L stainless steel
KW - Heat treatments
KW - Tensile properties
KW - Microstructure
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632471
DO - https://doi.org/10.1016/j.msea.2025.148469
SN - 0921-5093
VL - 939
SP - 1
EP - 24
PB - Elsevier
CY - Amsterdam
AN - OPUS4-63247
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Han, Ying
A1 - Schriever, Sina
A1 - von Hartrott, Philipp
A1 - Rockenhäuser, Christian
A1 - Skrotzki, Birgit
T1 - Creep dataset for aluminum alloy EN AW-2618A in the T61 and overaged condition 1000 h/190 °C
N2 - The article presents creep data for the precipitation-hardened aluminum alloy EN AW-2618A, which was tested in its initial slightly underaged T61 condition and after being aged at 190 °C for 1000 h. The creep test temperatures ranged between 160 °C and 230 °C, and the applied initial stresses between 40 MPa and 290 MPa. The testing times reached up to 4700 h. 19 data sets are provided as creep strain vs. time series. A data schema originally developed to manage creep reference data of a single-crystalline nickel-based superalloy was adapted for the research data set of the polycrystalline aluminum alloy and used to enrich the test data with extensive metadata. The dataset can be used to calibrate and validate creep models. The creep data supplement the hardness and microstructure data that have been previously published.
KW - Aluminum alloy EN AW-2618A
KW - Aging
KW - Overaging
KW - High temperature
KW - Creep
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641517
DO - https://doi.org/10.1016/j.dib.2025.112054
SN - 2352-3409
VL - 62
SP - 1
EP - 10
PB - Elsevier
CY - Amsterdam [u.a.]
AN - OPUS4-64151
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhadeliya, Ashok
A1 - Rehmer, Birgit
A1 - Skrotzki, Birgit
A1 - Jokisch, Torsten
A1 - Olbricht, Jürgen
A1 - Fedelich, Bernard
T1 - Fatigue crack growth in nickel-based alloy 247DS with side-brazed pre-sintered preform
N2 - Pre-sintered preform (PSP) brazing is employed in the repair of gas turbine components made of nickel-based alloys, including restoring the surface and dimensions of turbine blades and vanes. This study investigates the fatigue crack growth (FCG) behavior of Alloy 247DS specimens with side-brazed PSP material, mimicking a typical sandwich structure formed during such repairs. FCG tests were conducted at an elevated temperature of 950 °C and a stress ratio (R) of 0.1 on specimens with PSP layer thicknesses of 1.5 mm, 2 mm, 3 mm, and 4.5 mm to assess the influence of PSP thickness on fatigue crack growth behavior. Fractographic and metallographic analyses were performed to elucidate the underlying crack growth mechanisms and the microstructural characteristics of both materials. The results revealed that a crack consistently initiated in the PSP material, originating from the starter notch, particularly at the specimen corner during the pre-cracking phase. Additionally, crack propagation in the PSP material consistently advanced ahead of the crack in the Alloy 247DS. This crack growth behavior is attributed to the difference in elastic properties and microstructural differences between the PSP and base material. Metallographic analysis revealed the presence of porosity and brittle precipitates within the PSP material, which led to faster intergranular crack growth. Conversely, Alloy 247DS exhibited transgranular crack growth, contributing to the observed crack propagation behavior. This study demonstrates the applicability of standard FCG testing methods and an approach to characterize the FCG behavior in sandwich specimens, where crack growth occurs simultaneously in both materials, providing a preliminary understanding of crack growth behavior in Alloy 247DS with side-brazed PSP.
KW - High-temperature fatigue crack growth (FCG)
KW - Nickel-based alloys
KW - Alloy 247DS
KW - Pre-Sintered Preform (PSP)
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629783
DO - https://doi.org/10.1016/j.ijfatigue.2025.108961
VL - 197
SP - 1
EP - 13
PB - Elsevier BV
AN - OPUS4-62978
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chahal, Shweta
A1 - Xiao, Boyu
A1 - Grant, Jessica
A1 - Furniss, David
A1 - Farries, Mark
A1 - Phang, Sendy
A1 - Neate, Nigel
A1 - Robertson, Lorelei
A1 - Roe, Martin
A1 - Barney, Emma
A1 - Seddon, Angela B.
T1 - Ce3+-doped chalcogenide glass fibre for laser beyond 4 microns wavelength: Glass material-integrity
N2 - The 4-μm wavelength barrier encountered for mid-infrared fibre lasing based on heavy metal fluoride glasses has been overcome. We reported, in 2021, the first continuous wave, mid-infrared fibre laser operating beyond 4 μm at room temperature in a fibre with a Ce3+-doped selenide-chalcogenide core. Defects, such as crystallites in the core glass, could cause unwanted light-scattering, diminishing fibre laser efficiency. It is important to identify such optical loss mechanisms and eradicate them. Here, we report on investigating the material nano-structure of a chalcogenide-glass lasing fibre which exhibits 7 mW laser power output; the fibre has a Ce3+-doped core (8.5 μm diameter), concentrically surrounded by an inner- and outer-cladding, where both cladding-glasses are nominally the same composition. High resolution transmission electron microscopy and electron diffraction show that the core, inner-cladding and outer-cladding of the lasing fibre are internally nano-crystallite-free and amorphous. However, the external outer surface of the last 10 m of fibre drawn, of the total 100 m, contains monoclinic GeSe2 crystallites adjacent to discrete, small (<0.5 mm) wrinkled defects. The final length of fibre is drawn from the final part of the glass fibreoptic preform. The glass preform has as its outermost component an extruded chalcogenide glass tube. It is the last part of the tube which spends the longest time at high temperature inside the extruder during tube manufacture, encouraging heterogeneous nucleation at the tube outer-surface in contact with the extruder. These heterogeneous nuclei subsequently nucleate crystal growth during fibre-drawing in the outermost fibre surface.
KW - Optical glass
KW - Photonics
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653371
DO - https://doi.org/10.1016/j.optmat.2025.117219
SN - 0925-3467
VL - 166
SP - 1
EP - 14
PB - Elsevier
CY - Amsterdam
AN - OPUS4-65337
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schilling, Markus
A1 - Marschall, Niklas
A1 - Niebergall, Ute
A1 - Wachtendorf, Volker
A1 - Böhning, Martin
T1 - Unveiling Effects of Biodiesel and Diesel on Environmental Stress Cracking of PE-HD
N2 - The behavior of high‐density polyethylene with respect to resistance against environmental stress cracking (ESC) is usually regarded as an inherent material property being specific for respective types of PE‐HD and tested using standardized methods, conditions, and also standard testing liquids (usually aqueous surfactant solutions). On the other hand, for practical applications the ESC behavior of those polymeric materials, commonly used for pipes or containers, in contact with other liquids (e.g., fuels) is often of relevant interest, but for a reasonable assessment, where consistent benchmark data for a direct comparison are often missing, it is essential to determine the actually prevailing failure mode and classify it related to crack propagation or other mechanisms. Using the well‐established Full Notch Creep Test, which favorably allows for a detailed microscopic fracture surface analysis after failure, the behavior of two typical PE‐HD types for container applications is investigated in biodiesel and diesel and compared to a standard surfactant solution. This enables a clear identification of characteristic features of the interaction of biodiesel and diesel as sorptive fuels in contact with the polymer, revealing the complex interplay of sorption and plasticization as well as ESC inducing effects on PE‐HD, which could be clearly shown for both fuels.
KW - Biodiesel
KW - Confocal laser scanning microscopy (LSM)
KW - Diesel
KW - Full notch creep test (FNCT)
KW - Plasticization
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650525
DO - https://doi.org/10.1002/pen.70239
SN - 0032-3888
SP - 1
EP - 16
PB - Wiley
CY - Hoboken (NJ)
AN - OPUS4-65052
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Elfetni, Seif
A1 - Darvishi Kamachali, Reza
T1 - PINNs-MPF: A Physics-Informed Neural Network framework for Multi-Phase-Field simulation of interface dynamics
N2 - We present PINNs-MPF framework, an application of Physics-Informed Neural Networks (PINNs) to handle Multi-Phase-Field (MPF) simulations of microstructure evolution. A combination of optimization techniques within PINNs and in direct relation to MPF method are extended and adapted. The numerical resolution is realized through a multi-variable time-series problem by using fully discrete resolution. Within each interval, space, time, and phases/grains are treated separately, constituting discrete subdomains. PINNs-MPF is equipped with an extended multi-networking (parallelization) concept to subdivide the simulation domain into multiple batches, with each batch associated with an independent NN trained to predict the solution. To ensure continuity across the spatio-temporal-phasic subdomains, a Master NN efficiently is to handle interactions among the multiple networks and facilitates the transfer of learning. A pyramidal training approach is proposed to the PINN community as a dual-impact method: to facilitate the initialization of training when dealing with multiple networks, and to unify the solution through an extended transfer of learning. Furthermore, a comprehensive approach is adopted to specifically focus the attention on the interfacial regions through a dynamic meshing process, significantly simplifying the tuning of hyper-parameters, serving as a key concept for addressing MPF problems using machine learning. We perform a set of systematic simulations that benchmark foundational aspects of MPF simulations, i.e., the curvature-driven dynamics of a diffuse interface, in the presence and absence of an external driving force, and the evolution and equilibrium of a triple junction. The proposed PINNs-MPF framework successfully reproduces benchmark tests with high fidelity and Mean Squared Error (MSE) loss values ranging from 10^−6 to 10^−4 compared to ground truth solutions.
KW - Machine learning
KW - PINNs
KW - Phase-field method
KW - Microstructure evolution
KW - Parallel training
KW - Neural networks
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629740
DO - https://doi.org/10.1016/j.enganabound.2025.106200
SN - 0955-7997
VL - 176
SP - 1
EP - 22
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62974
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Elfetni, Seifallah
A1 - Darvishi Kamachali, Reza
T1 - PINNs-MPF: An Efficient Physics-Informed Machine Learning-based Solver for Multi-Phase-Field Simulations using Tensorflow
N2 - This paper introduces PINNs-MPF, a novel Machine Learning-based solver designed for Multi-Phase-Field (MPF) and diffuse interface simulations, offering innovative approaches to address complex challenges in addressing microstructure evolution in polycrystalline materials using Machine Learning. The framework not only surpasses current limitations in handling multi-phase problems but also allows for potential upscaling to tackle more intricate scenarios. Developed in Python, the related code leverages optimized libraries like TensorFlow, showcasing efficiency and potential scalability in materials science and engineering simulations. This framework, integrating advanced techniques such as multi-networking and training optimization, setting a new standard in predictive capabilities and understanding complex physical phenomena.
KW - Machine Learning
KW - Microstructure Simulation
KW - Phase Field
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631917
DO - https://doi.org/10.1016/j.simpa.2025.100753
SN - 2665-9638
VL - 24
SP - 1
EP - 4
PB - Elsevier B.V.
AN - OPUS4-63191
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Murugan, Jegatheesan
A1 - Darvishi Kamachali, Reza
T1 - High‑throughput investigation of grain boundary segregation landscape in the Fe–Ni–Cr system
N2 - Understanding phase stability in multicomponent alloy systems, particularly at internal interfaces, remains a major challenge in materials science. Grain boundary (co-)segregation is a critical factor influencing interfacial stability, often leading to microstructural degradation and safety concerns. In this study, we investigate segregation behavior in the face-centered cubic (FCC) Fe–Ni–Cr alloy system, a foundational system for many steels, superalloys, and high-entropy alloys. CALPHAD-integrated density-based phase-field model is extended to compute the segregation of Fe, Ni, and Cr at grain boundaries as a function of the bulk composition, with the relative GB density serving as a key parameter representing grain boundary character. A high-throughput computational screening is performed across the stable compositional space at 723 K, 1023 K, and 1323 K. The results reveal a rich and temperature-sensitive segregation landscape, with element-specific enrichment and depletion patterns that vary with alloy composition. Notably, opposite segregation trends between Ni and Cr, and frequent co-segregation of Fe and Ni, are observed at lower temperatures. The developed framework captures the coupled effects of temperature, chemical interactions, grain boundary structure, and enthalpy-entropy compensation on segregation and GB phase stability. The origin and implications of these phenomena are discussed in terms of the underlying thermodynamic driving forces.
KW - Segregation Engineering
KW - Grain boundary segregation
KW - Thermodynamics
KW - CALPHAD
KW - Fe--Ni--Cr alloys
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-646404
DO - https://doi.org/10.1007/s10853-025-11717-5
SN - 1573-4803
SP - 1
EP - 21
PB - Springer Science + Business Media
CY - Dordrecht [u.a.]
AN - OPUS4-64640
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Meira, Maria Fernanda Cavalcante
A1 - Fernandes, Gabriela Leal Peres
A1 - de Camargo, Andréa Simone Stucchi
A1 - Ravaro, Leandro Piaggi
A1 - Arai, Marylyn Setsuko
A1 - Navarro, Maria Fidela de Lima
A1 - Brighenti, Fernanda Lourenção
A1 - Oliveira, Analú Barros de
A1 - Danelon, Marcelle
ED - Stucchi de Camargo, Andrea
T1 - Modification of restorative glass ionomer cement with zinc oxide nanoparticles and calcium glycerophosphate microparticles: in vitro assessment of mechanical properties and antimicrobial activity
N2 - Abstract The incorporation of bioactive agents into resin-modified glass ionomer cement (RMGIC) is a promising strategy to improve its mechanical strength and biofilm control, especially for patients with active dental caries. Objective This study aimed to evaluate the effects of incorporating ZnONPs and CaGP into RMGIC on its mechanical and microbiological properties. Design Six groups were tested: 1) RMGIC (without CaGP/ZnONPs); 2) RMGIC-1.0%ZnONPs; 3) RMGIC-2.0%ZnONPs; 4) RMGIC-3.0%CaGP; 5) RMGIC-3.0%CaGP-1.0%ZnONPs; and 6) RMGIC-3.0%CaGP-2.0%ZnONPs. The compressive strength (CS), diametral tensile strength (DTS), and surface hardness (SH) were evaluated after 24 hours and 7 days. Antimicrobial and antibiofilm activity were evaluated using agar diffusion and biofilm metabolic activity (XTT) assays. Results After 24 hours, all the groups showed similar DTS values (p0.05), except for RMGIC-3.0%CaGP-1.0%ZnONPs, which showed the highest DTS value (p<0.05). Comparing 24 hours and 7 days, the DTS values of RMGIC-3.0%CaGP-2.0%ZnONPs, RMGIC-3.0%CaGP, and RMGIC-3.0%CaGP-2.0%ZnONPs were similar (p=0.360). After 24 hours, the RMGIC group showed the CS highest value, followed by RMGIC-2.0%ZnONPs (p < 0.05). After 7 days, the RMGIC-3.0%CaGP-1.0%ZnONPs group exhibited the highest CS value, approximately 15% higher than RMGIC (p<0.05). The RMGIC-1.0%ZnONPs group exhibited significantly higher SH at 24 hours (p=0.621). At 7 days, the highest SH value was observed for the RMGIC-3.0%CaGP-1.0%ZnONPs group (p<0.05). Regarding antimicrobial and antibiofilm activity, including results from biofilm metabolism assays, the RMGIC-3.0%CaGP-1.0%ZnONPs group demonstrated the most effective antimicrobial and inhibitory effects (p<0.05). Conclusion This study demonstrated that adding ZnONPs and CaGP to RMGIC enhanced its mechanical and antimicrobial and antibiofilm properties, suggesting enhanced mechanical performance and improved protection against cariogenic biofilms—critical factors for successful restorative treatments. Therefore, the addition of ZnONPs and CaGP is a promising strategy to develop advanced restorative materials that improve clinical outcomes, especially for patients with active dental caries.
KW - Resin-modified glass ionomer cement
KW - Phosphate
KW - Zinc oxide nanoparticles
KW - Biofilm
KW - Mechanical properties
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652799
DO - https://doi.org/10.1590/1678-7757-2025-0356
SN - 1678-7765
VL - 33
SP - 1
EP - 14
PB - FapUNIFESP (SciELO)
AN - OPUS4-65279
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arai, Marylyn S.
A1 - Brambilla, Gabriel V.
A1 - Corrêa, Bruna Carolina
A1 - Merízio, Leonnam G.
A1 - Inada, Natalia M.
A1 - de Camargo, Andrea S. S.
T1 - A Dual-Mode “Turn-On” Ratiometric Luminescent Sensor Based on Upconverting Nanoparticles for Detection and Differentiation of Gram-Positive and Gram-Negative Bacteria
N2 - Infectious bacterial diseases, intensified by antibiotic resistance, cause millions of deaths annually and pose risks beyond human health, including water and food contamination. Current diagnostics are often slow, require complex equipment, and lack specificity, highlighting the need for rapid and reliable detection methods. To address this, we developed a luminescent sensor based on NaYF4 upconverting nanoparticles (UCNPs) doped with Er3+ or Tm3+, coated with COOH-PEG4-COOH, and functionalized with vancomycin (Van) or polymyxin-B (Poly) to selectively target Gram-positive and Gram-negative bacteria, respectively. Gold nanoparticles (AuNPs) served as quenchers, enabling a ratiometric “turn-on” mechanism: upon bacterial binding, the UCNP emission, initially quenched by AuNPs, was partially restored. This allowed Differentiation through changes in the green/red (G/R) ratio for Er-UCNP@PEG4-Van and the blue/red (B/R) ratio for Tm-UCNP@PEG4-Poly. The sensor distinguished between Gram-positive and Gram-negative bacteria over a wide concentration range (0.05 to 5 × 105 CFU/mL) and showed high correlation with actual bacterial counts (r = 0.99 for S. aureus, r = 0.91 for E. coli). This platform is a potential fast, selective, and reliable tool for bacterial detection in clinical and environmental settings.
KW - Lminescent sensor
KW - Upconverting nanoparticles
KW - Gram-positive and Gram-negative bacteria
KW - Ratiometric luminescent sensors
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652785
DO - https://doi.org/10.1021/acsomega.5c07006
SN - 2470-1343
VL - 10
IS - 39
SP - 46040
EP - 46050
PB - American Chemical Society (ACS)
AN - OPUS4-65278
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Marschall, Niklas
A1 - Murugan, Jegatheesan
A1 - Darvishi Kamachali, Reza
T1 - Incorporating elasticity into the thermodynamics and phase diagrams of multi-component systems
N2 - Elastic energy plays a critical role in determining phase stability in compositionally complex alloys. However, quantifying elastic contributions in multi-component systems and incorporating them into phase diagram construction remain challenging. In this study, we present a generalized elastic energy formalism tailored for multi-component alloys, which can be directly and efficiently integrated with CALPHAD thermodynamic databases and existing frameworks such as Thermo-Calc (Andersson et al., 2002), Pandat (Cao et al., 2009) or FactSage (Bale et al., 2016). This elasticity formalism can also be introduced as a post-processing layer in open-source software such as pyCALPHAD (Otis and Liu, 2017) and Kawin (Ury et al., 2023) , enabling elastic assessments in multi-component systems. We apply our framework for constructing the phase diagram of quinary Fe–Mn–Ni–Co–Cu alloy system, utilizing convex hull and Hessian matrix under elastic considerations. Our results reveal that incorporating elastic energy leads to an expansion of both the spinodal region and the miscibility gap. These are governed by the intricate interplay of chemical and elastic driving forces: We found that Mn and Ni contribute strongly to chemical stabilization, while Cu and Co tend to destabilize the alloy, especially at low Mn concentrations. The stabilizing effect of Fe is also pronounced in Mn-deficient regions. Acting as a destabilizing factor, the elastic energy is primarily driven by the presence of Mn, underscoring its multifaceted role in thermodynamic stability. In Mn-rich compositions, Cu markedly reduces the elastic energy contribution. Combined with CALPHAD infrastructures, the current framework offers a practical pathway to improve the predictive accuracy of phase stability and transformations in complex multi-component alloys.
KW - Elastic energy
KW - HEA
KW - CALPHAD
KW - Elastic spinodal
KW - Elastic miscibility gap
KW - Elastic phase diagram
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643339
DO - https://doi.org/10.1016/j.mtla.2025.102546
SN - 2589-1529
VL - 44
SP - 1
EP - 18
PB - Elsevier
CY - Amsterdam, Niederlande
AN - OPUS4-64333
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arai, Marylyn Setsuko
A1 - Machado, Thales Rafael
A1 - da Silva, Beatriz Giacomelli Rodrigues
A1 - Vilela, Raquel Riciati do Couto
A1 - de Camargo, Andrea Simone Stucchi
A1 - Zucolotto, Valtencir
T1 - Biomimetic Upconverting Nanoplatforms for Glioblastoma Bioimaging and Targeted Therapy
N2 - Infectious bacterial diseases, intensified by antibiotic resistance, cause millions of deaths annually and pose risks beyond human health, including water and food contamination. Current diagnostics are often slow, require complex equipment, and lack specificity, highlighting the need for rapid and reliable detection methods. To address this, we developed a luminescent sensor based on NaYF4 upconverting nanoparticles (UCNPs) doped with Er3+ or Tm3+, coated with COOH-PEG4-COOH, and functionalized with vancomycin (Van) or polymyxin-B (Poly) to selectively target Gram-positive and Gram-negative bacteria, respectively. Gold nanoparticles (AuNPs) served as quenchers, enabling a ratiometric “turn-on” mechanism: upon bacterial binding, the UCNP emission, initially quenched by AuNPs, was partially restored. This allowed differentiation through changes in the green/red (G/R) ratio for Er-UCNP@PEG4-Van and the blue/red (B/R) ratio for Tm-UCNP@PEG4-Poly. The sensor distinguished between Gram-positive and Gram-negative bacteria over a wide concentration range (0.05 to 5 × 105 CFU/mL) and showed high correlation with actual bacterial counts (r = 0.99 for S. aureus, r = 0.91 for E. coli). This platform is a potential fast, selective, and reliable tool for bacterial detection in clinical and environmental settings.
KW - Glioblastoma
KW - Homotypic targeting
KW - Cell membrane coating
KW - Upconverting nanoparticles
KW - Temozolamide
KW - Near infrared bioimaging
KW - Drug delivery
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652808
DO - https://doi.org/10.1021/acsanm.5c04567
SN - 2574-0970
VL - 10
IS - 39
SP - 1
EP - 13
PB - American Chemical Society (ACS)
AN - OPUS4-65280
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - WójciaK, K.
A1 - Tokarski, T.
A1 - Cios, G.
A1 - Winkelmann, A.
A1 - Chulist, R.
A1 - Nolze, G.
T1 - Unconventional Applications of Electron Backscattering Diffraction (EBSD) in Metallic Materials
N2 - Electron backscattered diffraction is widely used for phase and orientation imaging of crystalline specimens. Despite the inherent complexity of diffraction images, current analysis methodologies typically focus on the position of Kikuchi bands or direct comparisons between experimental and simulated patterns. These approaches require prior knowledge of the phases to be analyzed, limiting their applicability in certain scenarios. This paper introduces an alternative methodology, crystallographic analysis of lattice metric, which extracts phase and orientation information directly from the registered diffraction pattern without requiring predefined standards. The paper outlines the methodology, discusses limitations, and demonstrates possible application in phase analysis, lattice parameter ratio mapping, and qualitative lattice distortion mapping.
KW - EBSD
KW - Virtual dark-field imaging
KW - Lattice distortion
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656014
DO - https://doi.org/10.24425/amm.2025.156241
VL - 70
IS - 4
SP - 1619
EP - 1626
AN - OPUS4-65601
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Andreoli, A. F.
A1 - Fantin, Andrea
A1 - Kasatikov, S.
A1 - Bacurau, V. P.
A1 - Widom, M.
A1 - Gargarella, P.
A1 - Mazzer, E. M.
A1 - Woodcock, T. G.
A1 - Nielsch, K.
A1 - Coury, F. G.
T1 - The impact of chemical short-range order on the thermophysical properties of medium- and high-entropy alloys
N2 - The unusual behavior observed in the coefficient of thermal expansion and specific heat capacity of CrFeNi, CoCrNi, and CoCrFeNi medium/high-entropy alloys is commonly referred to as the K-state effect. It is shown to be independent of the Curie temperature, as demonstrated by temperature-dependent magnetic moment measurements. CoCrFeNi alloy is chosen for detailed characterization; potential reasons for the K-state effect such as texture, recrystallization, and second-phase precipitation are ruled out. An examination of the electronic structure indicates the formation of a pseudo-gap in the Density of States, which suggests a specific chemical interaction between Ni and Cr atoms upon alloying. Hybrid Monte Carlo/Molecular Dynamic (MC/MD) simulations indicate the presence of non-negligible chemical short-range order (CSRO). Local lattice distortions are shown to be negligible, although deviations around Cr and Ni elements from those expected in a fully disordered structure are experimentally observed by X-ray absorption spectroscopy. The determined bonding distances are in good agreement with MC/MD calculations. A mechanism is proposed to explain the anomalies and calorimetric experiments and their results are used to validate the mechanism.
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - General Materials Science
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595869
DO - https://doi.org/10.1016/j.matdes.2024.112724
SN - 0264-1275
VL - 238
SP - 1
EP - 15
PB - Elsevier B.V.
AN - OPUS4-59586
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Blaeß, Carsten
A1 - Müller, Ralf
A1 - Boccaccini, A. R.
T1 - Sintering and crystallization kinetics of bioactive glass 13-93
N2 - This study investigates the sintering and crystallization behavior and kinetic of the bioactive glass (BG) 13–93 with nominal composition (in mol%): 54.6 SiO2 - 1.7 P2O3 - 22.1 CaO - 6.0 Na2O - 7.9 K2O - 7.7 MgO. Sintering and crystallization were investigated non-isothermally for various particle size fractions smaller than 315 μm as well as for bulk samples. Densification was not hindered by the presence of crystalline phases across all particle size fractions. Afterwards, wollastonite was found as the dominant crystal phase at higher temperature which resorb primary surface precipitation-like quartz crystallites. The growth direction shifts into volume when the sample surface is nearly covered. The crystal growth rate of wollastonite was calculated from the crystalline surface layer thickness measured during heating. The findings of this study are relevant for the high temperature processing of BG 13–93.
KW - Bioactive glass
KW - Sintering
KW - Crystallization
PY - 2024
DO - https://doi.org/10.1016/j.jnoncrysol.2023.122790
SN - 0022-3093
VL - 627
SP - 1
EP - 7
PB - Elsevier
AN - OPUS4-59337
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - Birkholz, Henk
A1 - Jung, Matthias
A1 - Waitelonis, Jörg
A1 - Mädler, Lutz
A1 - Sack, Harald
T1 - PMD Core Ontology: Achieving semantic interoperability in materials science
N2 - Knowledge representation in the Materials Science and Engineering (MSE) domain is a vast and multi-faceted challenge: Overlap, ambiguity, and inconsistency in terminology are common. Invariant (consistent) and variant (context-specific) knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific. In this paper, an approach how to maintain a comprehensive MSE-centric terminology composing a mid-level ontology–the Platform MaterialDigital Core Ontology (PMDco)–via MSE community-based curation procedures is presented. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics. Additionally, it demonstrates how the PMDco lowers development and integration thresholds. Moreover, the research highlights how to fuel it with real-world data sources ranging from manually conducted experiments and simulations with continuously automated industrial applications.
KW - Ontology
KW - Materials science and engineering
KW - Knowledge representation
KW - Reproducibility
KW - Semantic interoperability
KW - Semantic data integration
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592948
DO - https://doi.org/10.1016/j.matdes.2023.112603
SN - 0264-1275
VL - 237
SP - 1
EP - 12
PB - Elsevier
CY - Amsterdam
AN - OPUS4-59294
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lemiasheuski, Anton
A1 - Kranzmann, Axel
A1 - Pfennig, Anja
T1 - Herausforderungen und Möglichkeiten des manuellen metallografischen Serienschnittverfahrens anhand einer quantitativen Gefügeanalyse der Grafite eines Gusseisens
T1 - Challenges and possibilities of the manual metallographic serial sectioning process using the example of a quantitative microstructural analysis of graphite in cast iron
N2 - Die in dieser Studie vorgestellte 3D-Gefüge-Analyse konzentriert sich auf die Kugelgrafite eines Gusseisens des Typs EN-GJS. Es werden die Form anhand des Formfaktors und des Seitenverhältnisses sowie die durchschnittliche Teilchengröße und -verteilung untersucht.
Die Form der Grafite in Gusseisenwerkstoffen ist mitentscheidend für die mechanischen Eigenschaften dieser Legierungen und ist bei der Charakterisierung des Werkstoffs unumgänglich. Mittels Metallografischen Serienschnittverfahrens wird von dem Schicht für Schicht abgetragenen und lichtmikroskopisch schichtweise dargestellten Werkstoff ein digitaler Zwilling erstellt. Von diesem dreidimensionalen Zwilling lassen sich beliebige Ebenen digital projizieren und analysieren. Eine konventionelle quantitative 3D-Analyse untersucht die Voxelmenge und -zusammensetzung eines Körpers im 3D-Raum. Die hier vorgestellte Analyse wendet stereologische 2D-Analyseverfahren auf drei Raumebenen des Werkstoffs an. Dabei sind zwei der Ebenen digitale Projektionen des Zwillings. Die zwei rekonstruierten Ebenen des Werkstoffs sind so gewählt, dass die Richtungsvektoren aller drei Ebenen einen 90°-Winkel zueinander bilden. Diese Methodik wird eingehend beschrieben sowie Herausforderungen und Möglichkeiten des hier vorgestellten Serienschnittverfahrens diskutiert.
N2 - The 3D microstructure analysis presented in this study focuses on the nodular graphite of an EN-GJS grade cast iron. The shape is analyzed based on shape factor and aspect ratio as well as average particle size and distribution. The shape of graphites in cast iron materials is critical to the mechanical properties of these alloys and is essential for the characterization of the material. Metallographic serial sectioning creates a digital twin of the material, which is removed layer by layer and visualized layer by layer under an optical microscope. From this three-dimensional twin, any number of planes can be digitally projected and analyzed. Conventional quantitative 3D analysis examines the voxel count and composition of a body in 3D space. The analysis presented here applies stereological 2D analysis methods to three spatial planes of the material. Two of the planes are digital projections of the twin. The two reconstructed planes of the material are chosen so that the direction vectors of all three planes form an angle of 90° to each other. The methodology is described in detail and the challenges and opportunities of the serial section method presented here are discussed.
KW - Dreidimensionale Gefügeanalyse
KW - Three-dimensional microstructure analysis
KW - 3D-Metallografie
KW - Serienschnittverfahren
KW - Gefügerekonstruktion
KW - Quantitative Gefügeanalyse
KW - 3D metallography
KW - Serial sectioning
KW - Microstructure reconstruction
KW - Quantitative microstructure analysis
PY - 2024
DO - https://doi.org/10.1515/pm-2024-0066
SN - 0032-678X
VL - 61
IS - 9-10
SP - 746
EP - 768
PB - De Gruyter
CY - Berlin/Boston
AN - OPUS4-60976
LA - mul
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bacurau, V. P.
A1 - Moreira, P. A. F. P.
A1 - Bertoli, G.
A1 - Andreoli, A. F.
A1 - Mazzer, E.
A1 - de Assis, F. F.
A1 - Gargarella, P.
A1 - Koga, G.
A1 - Stumpf, G. C.
A1 - Figueroa, S. J. A.
A1 - Widom, M.
A1 - Kaufman, M.
A1 - Fantin, Andrea
A1 - Cao, Y.
A1 - Freitas, R.
A1 - Miracle, D.
A1 - Coury, F. G.
T1 - Comprehensive analysis of ordering in CoCrNi and CrNi2 alloys
N2 - Chemical Short-Range Order (CSRO) has attracted recent attention from many researchers, creating intense debates about its impact on material properties.
The challenges lie in confirming and quantifying CSRO, as its detection proves exceptionally demanding, contributing to conflicting data in the literature regarding its true effects on mechanical properties. Our work uses highprecision calorimetric data to unambiguously prove the existence and, coupled with atomistic simulations, quantify the type of CSRO. This methodology allows us to propose a mechanism for its formation and destruction based on the heat evolution during thermal analysis and facilitates a precise identification of local ordering in CoCrNi alloys. Samples of CoCrNi (Co33Cr33Ni33) and CrNi2 (Cr33Ni66) alloys are fabricated in varying ordered states, extensively characterized via synchrotron X-ray diffraction, X-ray absorption spectroscopy, and transmission electron microscopy. Samples with considerably different ordered states are submitted to tensile tests with in-situ synchrotron X-ray diffraction. We demonstrate, despite inducing varied CSRO levels in CoCrNi, no significant alterations in overall mechanical behavior emerge.
However, the CrNi2 alloy, which undergoes long-range ordering, experiences significant shifts in yield strength, ultimate tensile stress and ductility.
KW - Mechanical properties
KW - Short-range ordering
KW - Calorimetry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611075
DO - https://doi.org/10.1038/s41467-024-52018-w
VL - 15
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-61107
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gaddam, Anuraag
A1 - Galleani, Gustavo
A1 - de Lima Reis, Vitor
A1 - de Camargo, Andrea S. S.
A1 - Eckert, Hellmut
T1 - Structural characterization of gallium fluoride phosphate glasses by advanced solid‐state NMR methods and correlation with photophysical properties
N2 - AbstractGallium fluoride phosphate glasses feature low refractive index, high energy radiation resistance, wide transmission range, and favorable emission characteristics of rare‐earth dopants. For the development of optimized glass compositions, a fundamental understanding of these properties in terms of glass structure is sought. We report nuclear magnetic resonance (NMR) structural studies of glasses in the system xGa(PO3)3–(40 − x)GaF3–20BaF2–20ZnF2–20SrF2 (x = 5, 10, 15, 20, and 25 mol%). 31P NMR results with 71Ga recoupling show that the network structure is dominated by P–O–Ga linkages, and no P–O–P linkages exist. 71Ga NMR results show that Ga is mainly six‐coordinated featuring a mixed fluoride/phosphate coordination. Quantitative estimates of this ligand distribution around gallium were obtained by 71Ga{31P} spin echo double resonance (REDOR) measurements. Photophysical properties suggest changes in the Eu(III) ligand distribution toward a fluoride‐dominated environment at low P/F ratio while the glass network is largely sustained by bridging oxygen atoms via P–O–Ga linkages.
KW - Gallium
KW - Glass
KW - NMR
KW - Oxyfluoride
PY - 2024
DO - https://doi.org/10.1111/jace.20051
SN - 0002-7820
SP - 1
EP - 14
PB - Wiley
AN - OPUS4-60785
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Merízio, Leonnam Gotardo
A1 - Machado, Ian Pompermayer
A1 - Vastamäki, Roosa
A1 - de Camargo, Andréa Simone Stucchi
A1 - Lastusaari, Mika
T1 - Multifunctional persistent luminescent and photochromic hackmanite-based materials prepared by microwave-assisted solid-state synthesis
N2 - Advanced optical materials inspired by natural minerals and non-toxic light elements, such as the Hackmanites (Na8Al6Si6O24(Cl,S)2), find vast possibilities of applications as they can simultaneously perform photochromism and persistent luminescence (PersL). In this work, we have explored a rapid and energy-efficient microwaveassisted (MASS) methodology for the synthesis of PersL and photochromic hackmanites. In addition, we have prepared hackmanite materials using a zeolite-free precursor to control the Na–Al–Si ratio and study its influence on the materials photoluminescent properties. The PersL hackmanites showed a white-bluish emission color, with up to 2 h of emission time. Zeolite-free photochromic materials were able to change the color from white to purple/blue efficiently with a few seconds of 254 nm excitation, but the usage of zeolite precursors enhanced the overall optical performance. Microwave synthesis times of 10–40 min were demonstrated to be optimal, as longer times boosted the formation of nepheline spurious phase, which decreases luminescence efficiency. In this way, the MASS method led to a reduction of reaction time up to 98 %, yielding hackmanite materials with similar photoluminescent or photochromic properties compared to those obtained by a 24 h conventional solid-state synthesis. This work represents a significant improvement toward coupling eco-friendly synthetic processes to
eco-friendly solid-state materials for PersL illumination and PersL/photochromism optical marking.
KW - Hackmanite
KW - Persistent luminescence
KW - Photochromism
KW - Microwave-assisted synthesis
PY - 2024
DO - https://doi.org/10.1016/j.optmat.2024.115826
SN - 0925-3467
VL - 155
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-60787
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cios, G.
A1 - Winkelmann, A.
A1 - Nolze, Gert
A1 - Tokarski, T.
A1 - Jany, B. R.
A1 - Bala, P.
T1 - EBSD and TKD analyses using inverted contrast Kikuchi diffraction patterns and alternative measurement geometries
N2 - Electron backscatter diffraction (EBSD) patterns can exhibit Kikuchi bands with inverted contrast due to anomalous absorption. This can be observed, for example, on samples with nanoscale topography, in case of a low tilt backscattering geometry, or for transmission Kikuchi diffraction (TKD) on thicker samples. Three examples are discussed where contrast-inverted physics-based simulated master patterns have been applied to find the correct crystal orientation. As first EBSD example, self-assembled gold nanostructures made of Au fcc and Au hcp phases on single-crystal germanium were investigated. Gold covered about 12% of the mapped area, with only two thirds being successfully interpreted using standard Hough-based indexing. The remaining third was solved by brute force indexing using a contrast-inverted master pattern. The second EBSD example deals with maps collected at a non-tilted surface instead of the commonly used 70◦ tilted one. As TKD example, a jet-polished foil made of duplex stainless steel 2205 was examined. The thin part close to the hole edge producing normal-contrast patterns were standard indexed. The areas of the foil that become thicker with increasing distance from the edge of the hole produce contrast-inverted patterns. They covered three times the evaluable area and were successfully processed using the contrast-inverted master pattern. In the last example, inverted patterns collected at a non-tiled sample were mathematically inverted to normal contrast, and Hough/Radon-based indexing was successfully applied.
KW - EBSD
KW - TKD
KW - Contrast inversion
KW - Topography
KW - Kikuchi diffraction
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613862
VL - 267
SP - 1
EP - 8
PB - Elsevier
CY - Amsterdam
AN - OPUS4-61386
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schilling, Markus
A1 - Bruns, Sebastian
A1 - Bayerlein, Bernd
A1 - Kryeziu, Jehona
A1 - Schaarschmidt, Jörg
A1 - Waitelonis, Jörg
A1 - Dolabella Portella, Pedro
A1 - Durst, Karsten
T1 - Seamless Science: Lifting Experimental Mechanical Testing Lab Data to an Interoperable Semantic Representation
N2 - The scientific landscape is undergoing rapid transformations with the advent of the digital age which revolutionizes research methodologies. In materials science and engineering, an adoption of modern data management techniques is desirable to maximize the efficiency and accessibility of research efforts. Traditional practices in testing laboratories are usually inadequate for efficient data acquisition and utilization as they lead to local storage and difficulty in publication and correlation with other results. Electronic laboratory notebooks (ELNs) are promising prospects in this respect. Semantic concepts and ontologies enhance interoperability by standardizing experimental data representation. An in‐laboratory pipeline seamlessly integrating an ELN with transformation scripts to convert experimental into interoperable data in a machine‐actionable format is created in this study as a proof of concept. Tensile test results and the corresponding tensile test ontology are used exemplary. Linking ELN data to semantic concepts enriches the stored information while improving interpretability and reusability. Involving undergraduate students builds a bridge between theory and practice during their training and promotes their digital skills. This study underscores the potential of ELNs and knowledge representations as beneficial means toward improved data management practices that enhance collaborative research and education while ensuring compatibility with evolving standards and technologies.
KW - Semantic Data
KW - Data Integration
KW - Tensile Test Ontology
KW - Electronic Lab Notebook
KW - Wissensrepräsentation
KW - Education
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618251
DO - https://doi.org/10.1002/adem.202401527
SP - 1
EP - 13
PB - Wiley VHC-Verlag
AN - OPUS4-61825
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavasarytė, Lina
A1 - Azevedo do Nascimento, Allana
A1 - Cysne Barbosa, Ana Paula
A1 - Trappe, Volker
A1 - Melo, Daniel
T1 - Effects of particle size and particle concentration of poly (ethylene-co-methacrylic acid) on properties of epoxy resin
N2 - Self-healing polymers have been developed to improve durability and reduce costs associated with maintenance during service. The addition of thermoplastics to thermosets to produce mendable polymers appears as a promising selfhealing technique. In this study, poly (ethylene-co-methacrylic acid) (EMAA) was added to epoxy resin and the effects of EMAA addition on epoxy properties were evaluated. Specimens with two different contents of thermoplastic and particles sizes were manufactured. A two-level full factorial experimental design was used to evaluate the effect of particle size and particle content on properties of epoxy modified with addition of EMAA. Tensile tests and dynamic mechanical analysis (DMA) were used and the evaluated responses were tensile strength, modulus of elasticity, and glass transition temperature (Tg). X-ray computed tomography (XCT) was used to investigate particle size and concentration after manufacturing. It was found that the particle concentration has greater effects on stress–strain behavior of epoxy while Tg was not significantly affected by neither of the analyzed entrance variables.
KW - Fracture
KW - Self-healing
KW - Epoxy
KW - Thermoplastic
PY - 2024
DO - https://doi.org/10.1002/app.55677
SN - 0021-8995
SP - 1
EP - 14
PB - Wiley online library
AN - OPUS4-60205
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - Curran, Maurice
A1 - Campbell, Carelyn E.
A1 - Dima, Alden A.
A1 - Birkholz, Henk
A1 - Lau, June W.
T1 - Natural Language Processing-Driven Microscopy Ontology Development
N2 - AbstractThis manuscript describes the accelerated development of an ontology for microscopy in materials science and engineering, leveraging natural language processing (NLP) techniques. Drawing from a comprehensive corpus comprising over 14 k contributions to the Microscopy and Microanalysis conference series, we employed two neural network-based algorithms for NLP. The goal was to semiautomatically create the Microscopy Ontology (MO) that encapsulates and interconnects the terminology most frequently used by the community. The MO, characterized by its interlinked entities and relationships, is designed to enhance the quality of user query results within NexusLIMS. This enhancement is facilitated through the concurrent querying of related terms and the seamless integration of logical connections.
KW - Microscopy Ontology
KW - Knowledge Representation
KW - Semantic Interoperability
KW - Natural Language Processing
KW - Ontology Development
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-616942
DO - https://doi.org/10.1007/s40192-024-00378-y
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-61694
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pfennig, Anja
A1 - Mohring, Wencke
A1 - Wolf, Marcus
T1 - The insignificant improvement of corrosion and corrosion fatigue behavior in geothermal environment applying Boehmit coatings on high alloyed steels
N2 - The efficacy of alumina-sol based coatings in a water-free atmosphere at high temperatures suggests a potential solution for enhancing the corrosion resistance of high-alloyed steels in Carbon Capture and Storage (CCS) environments. In this study, coupons of X20Cr13, designed for use as injection pipes with 13% Chromium and 0.20% Carbon (1.4021, AISI 420), were sol-gel coated with water and ethanol-based alumina. These coated coupons were then exposed to CO2-saturated saline aquifer water, simulating conditions in the Northern German Basin, for 1000 h at ambient pressure and 60 °C. Corrosion fatigue experiments were also conducted using specimens of X5CrNiMoCuNb16-4 (1.4542, AISI 630), a suitable candidate for geothermal applications, to assess the impact of the ethanol-based coating on the number of cycles to failure at different stress amplitudes. Unfortunately, the coating exhibited early spallation, resulting in corrosion kinetics and corrosion fatigue data identical to those of uncoated specimens. Consequently, the initially promising Boehmit coating is deemed unsuitable for CCS applications and further research therefore not advisable.
KW - Alumina coating
KW - High alloyed steel
KW - Pitting
KW - Surface corrosion
KW - CO2
KW - Pipeline
KW - Corrosion
KW - CCS
KW - CO2-storage
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623786
DO - https://doi.org/10.3390/app14041575
SN - 2076-3417
VL - 14
IS - 4
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-62378
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Alem, Sayed Ali Ahmad
A1 - Sabzvand, Mohammad Hossein
A1 - Govahi, Parnian
A1 - Poormehrabi, Pooria
A1 - Azar, Mahdi Hasanzadeh
A1 - Siouki, Sara Salehi
A1 - Rashidi, Reza
A1 - Angizi, Shayan
A1 - Bagherifard, Sara
T1 - Advancing the next generation of high-performance metal matrix composites through metal particle reinforcement
N2 - Metal matrix composites (MMCs) offer asignificant boost to achieve a wide range of advanced mechanical properties and improved performance for a variety of demanding applications. The addition of metal particles as reinforcement in MMCs is an exciting alternative to conventional ceramic reinforcements, which suffer from numerous shortcomings. Over the last two decades, various categories of metal particles, i.e., intermetallics, bulk metallic glasses, high-entropy alloys, and shape memory alloys, have become popular as reinforcement choices for MMCs. These groups of metal particles offer a combination of outstanding physico-mechanical properties leading to unprecedented performances; moreover, they are significantly more compatible with the metal matrices compared to traditional ceramic reinforcements. In this review paper, the recent developments in MMCs are investigated. The importance of understanding the active mechanisms at the interface of the matrix and the reinforcement is highlighted. Moreover, the processing techniques required to manufacture high-performance MMCs are explored identifying the potential structural and functional applications. Finally, the potential advantages and current challenges associated with the use of each reinforcement category and the future developments are critically discussed. Based on the reported results, the use of metal particles as reinforcement in MMCs offers a promising avenue for the development of advanced materials with novel mechanical properties. Further progress requires more in-depth fundamental research to realize the active reinforcing mechanisms at the atomic level to precisely identify, understand, and tailor the properties of the integrated composite materials.
KW - Intermetallic
KW - Composite
KW - Metal matrix composite
KW - Interface
KW - High entropy alloy
KW - Bulk metallic glass
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620730
DO - https://doi.org/10.1007/s42114-024-01057-4
SN - 2522-0128
VL - 8
IS - 1
SP - 1
EP - 68
PB - Springer Nature
AN - OPUS4-62073
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Was, G.S.
A1 - Bahn, C.-B.
A1 - Busby, J.
A1 - Cui, B.
A1 - Farkas, D.
A1 - Gussev, M.
A1 - Rigen He, M.
A1 - Hesterberg, J.
A1 - Jiao, Z.
A1 - Johnson, D.
A1 - Kuang, W.
A1 - McMurtrey, M.
A1 - Robertson, I.
A1 - Sinjlawi, A.
A1 - Song, M.
A1 - Stephenson, K.
A1 - Sun, K.
A1 - Swaminathan, Srinivasan
A1 - Wang, M.
A1 - West, E.
T1 - How irradiation promotes intergranular stress corrosion crack initiation
N2 - Irradiation assisted stress corrosion cracking (IASCC) is a form of intergranular stress corrosion cracking that occurs in irradiated austenitic alloys. It requires an irradiated microstructure along with high temperature water and stress. The process is ubiquitous in that it occurs in a wide range of austenitic alloys and water chemistries, but only when the alloy is irradiated. Despite evidence of this degradation mode that dates back to the 1960s, the mechanism by which it occurs has remained elusive. Here, using high resolution electron backscattering detection to analyze local stress-strain states, high resolution transmission electron microscopy to identify grain boundary phases at crack tips, and decoupling the roles of stress and grain boundary oxidation, we are able to unfold the complexities of the phenomenon to reveal the mechanism by which IASCC occurs. The significance of the findings impacts the mechanical integrity of core components of both current and advanced nuclear reactor designs worldwide.
KW - Irradiation
KW - Stress corrosion cracking
KW - Grain boundaries
KW - Oxidation
KW - Austenitic alloys
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595748
DO - https://doi.org/10.1016/j.pmatsci.2024.101255
SN - 0079-6425
VL - 143
SP - 1
EP - 15
PB - Elsevier
AN - OPUS4-59574
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nawaz, Q.
A1 - Blaeß, Carsten
A1 - Mueller, Ralf
A1 - Boccaccini, A.R.
T1 - Processing and cytocompatibility of Cu-doped and undoped fluoride-containing bioactive glasses
N2 - Sintered or additive-manufactured bioactive glass (BG) scaffolds are highly interesting for bone replacement applications. However, crystallization often limits the high-temperature processability of bioactive glasses (BGs). Thus, the BG composition must combine high bioactivity and processability. In this study, three BGs with nominal molar (%) compositions 54.6SiO2-1.7P2O3-22.1CaO-6.0Na2O-7.9K2O-7.7MgO (13–93), 44.8SiO2-2.5P2O3-36.5CaO-6.6Na2O-6.6K2O-3.0CaF2 (F3) and 44.8SiO2-2.5P2O3-35.5CaO-6.6Na2O-6.6K2O-3.0CaF2-1.0CuO (F3–Cu) were investigated. The dissolution and ion release kinetics were investigated on milled glass powder and crystallized particles (500–600 μm). All glasses showed the precipitation of hydroxyapatite (HAp) crystals after 7 days of immersion in simulated body fluid. No significant differences in ion release from glass and crystalline samples were detected. The influence of surface roughness on cytocompatibility and growth of preosteoblast cells (MC3T3-E1) was investigated on sintered and polished BG pellets. Results showed that sintered BG pellets were cytocompatible, and cells were seen to be well attached and spread on the surface after 5 days of incubation. The results showed an inverse relation of cell viability with the surface roughness of pellets, and cells were seen to attach and spread along the direction of scratches.
KW - Bioactive glass
KW - Crystallization
KW - Solubility
KW - Cytocompatibility
KW - Surface roughness
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598257
DO - https://doi.org/10.1016/j.oceram.2024.100586
SN - 2666-5395
VL - 18
SP - 1
EP - 8
PB - Elsevier Ltd.
AN - OPUS4-59825
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - von Hartrott, Philipp
A1 - Waitelonis, Jörg
T1 - Semantic integration of diverse data in materials science: Assessing Orowan strengthening
N2 - AbstractThis study applies Semantic Web technologies to advance Materials Science and Engineering (MSE) through the integration of diverse datasets. Focusing on a 2000 series age-hardenable aluminum alloy, we correlate mechanical and microstructural properties derived from tensile tests and dark-field transmission electron microscopy across varied aging times. An expandable knowledge graph, constructed using the Tensile Test and Precipitate Geometry Ontologies aligned with the PMD Core Ontology, facilitates this integration. This approach adheres to FAIR principles and enables sophisticated analysis via SPARQL queries, revealing correlations consistent with the Orowan mechanism. The study highlights the potential of semantic data integration in MSE, offering a new approach for data-centric research and enhanced analytical capabilities.
KW - Semantic Interoperability
KW - Knowledge Graph
KW - Orowan Mechanism
KW - Aluminum Alloy Aging
KW - Ontology
KW - Semantic Data Integration
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599780
DO - https://doi.org/10.1038/s41597-024-03169-4
VL - 11
IS - 1
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-59978
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - da Costa, P. F. G. M.
A1 - Merízio, L. G.
A1 - Wolff, N.
A1 - Terraschke, H.
A1 - de Camargo, Andrea Simone Stucchi
T1 - Real-time monitoring of CdTe quantum dots growth in aqueous solution
N2 - Quantum dots (QDs) are remarkable semiconductor nanoparticles, whose optical properties are strongly size-dependent. Therefore, the real-time monitoring of crystal growth pathway during synthesis gives an excellent opportunity to a smart design of the QDs luminescence. In this work, we present a new approach for monitoring the formation of QDs in aqueous solution up to 90 °C, through in situ luminescence analysis, using CdTe as a model system. This technique allows a detailed examination of the evolution of their light emission. In contrast to in situ absorbance analysis, the in situ luminescence measurements in reflection geometry are particularly advantageous once they are not hindered by the concentration increase of the colloidal suspension. The synthesized particles were additionally characterized using X-ray diffraction analysis, transition electron microscopy, UV-Vis absorption and infrared spectroscopy. The infrared spectra showed that 3-mercaptopropionic acid (MPA)-based thiols are covalently bound on the surface of QDs and microscopy revealed the formation of CdS. Setting a total of 3 h of reaction time, for instance, the QDs synthesized at 70, 80 and 90 °C exhibit emission maxima centered at 550, 600 and 655 nm. The in situ monitoring approach opens doors for a more precise achievement of the desired emission wavelength of QDs.
KW - CdTe quantum dots
KW - In situ synthesis
KW - Real time growth control
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603596
DO - https://doi.org/10.1038/s41598-024-57810-8
SN - 2045-2322
VL - 14
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-60359
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zhang, Fengchan
A1 - Oiticica, Pedro Ramon Almeida
A1 - Abad-Arredondo, Jaime
A1 - Arai, Marylyn Setsuko
A1 - Oliveira, Osvaldo N.
A1 - Jaque, Daniel
A1 - Fernandez Dominguez, Antonio I.
A1 - de Camargo, Andrea Simone Stucchi
A1 - Haro-González, Patricia
T1 - Brownian Motion Governs the Plasmonic Enhancement of Colloidal Upconverting Nanoparticles
N2 - Upconverting nanoparticles are essential in modern photonics due to their ability to convert infrared light to visible light. Despite their significance, they exhibit limited brightness, a key drawback that can be addressed by combining them with plasmonic nanoparticles. Plasmon-enhanced upconversion has been widely demonstrated in dry environments, where upconverting nanoparticles are immobilized, but constitutes a challenge in liquid media where Brownian motion competes against immobilization.
This study employs optical tweezers for the three-dimensional manipulation of an individual upconverting nanoparticle, enabling the exploration of plasmon-enhanced upconversion luminescence in water. Contrary to expectation, experiments reveal a long-range (micrometer scale) and moderate (20%) enhancement in upconversion luminescence due to the plasmonic resonances of gold nanostructures. Comparison between experiments and numerical simulations evidences the key role of Brownian motion. It is demonstrated how the three-dimensional Brownian fluctuations of the upconverting nanoparticle lead to an “average effect” that explains the magnitude and spatial extension of luminescence enhancement.
KW - Upconversion
KW - Plasmon enhancement
KW - Optical tweezers
KW - Brownian motion
KW - Nanoparticles
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603551
DO - https://doi.org/10.1021/acs.nanolett.4c00379
VL - 24
IS - 12
SP - 3785
EP - 3792
PB - American Chemical Society (ACS)
AN - OPUS4-60355
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ulrich, A. S.
A1 - Kasatikov, S.
A1 - König, T.
A1 - Fantin, Andrea
A1 - Margraf, J. T.
A1 - Galetz, M. C.
T1 - Decreased Metal Dusting Resistance of Ni-Cu Alloys by Fe and Mn Additions
N2 - Ni-Cu alloys are promising for application at temperatures between 400–900 °C and reducing atmospheres with high C-contents. Typically, under such conditions, metallic materials in contact with the C-rich atmosphere are degraded by a mechanism called metal dusting (MD). Ni-Cu-alloys do not form protective oxide scales, but their resistance is attributed to Cu, which catalytically inhibits the C-deposition on the surface. Adding other alloying elements, such as Mn or Fe, was found to enhance the MD attack of Ni-Cu alloys again. In this study, the effect of the Mn and Fe is divided into two affected areas: the surface and the bulk. The MD attack on binary Ni-Cu alloys, model alloys with Fe and Mn additions, and commercial Monel Alloy 400 is experimentally demonstrated. The surface electronic structure causing the adsorption and dissociation of C-containing molecules is investigated for model alloys. Analytical methods such as scanning electron microscopy combined with energy-dispersive X-ray spectroscopy, electron probe microanalysis combined with wavelength-dispersive X-ray spectroscopy, X-ray diffraction analysis, and near-edge X-ray absorption fine structure measurements were used. The results are correlated to CALPHAD calculations and atomistic simulations combining density functional theory calculations and machine learning. It is found that the Cu content plays a significant role in the surface reaction. The effect of Mn and Fe is mainly attributed to oxide formation. A mechanism explaining the enhanced attack by adding both Fe and Mn is proposed.
KW - Metal Dusting
KW - XANES
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608226
DO - https://doi.org/10.1007/s11085-024-10263-w
SN - 2731-8397
SP - 1
EP - 14
PB - Springer Science and Business Media LLC
AN - OPUS4-60822
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bordeenithikasem, Punnathat
A1 - Carpenter, Kalind C.
A1 - Hofmann, Douglas C.
A1 - White, Victor E.
A1 - Yee, Karl Y.
A1 - Rizzardi, Quentin
A1 - Maher, Jacob
A1 - Maaß, Robert
T1 - Miniaturized bulk metallic glass gripping structures for robotic mobility platforms
N2 - Advancements in bulk metallic glass thermoplastic forming unleash the potential to fabricate microscale metallic features with unparalleled precision and durability, i.e. microspine gripping structures for mobility platforms on planetary or in-space robots. Four designs of grippers were fabricated and rigorously tested. Coefficient of friction on four test surfaces were measured and compared to SiC paper and Velcro. The hardness and elasticity of the bulk metallic glasses make them a game-changer in the field, offering a superior alternative to conventional nonmetallic grippers.
KW - Bulk metallic glasses
KW - Thermoplastic forming
KW - Mobility
KW - Microspine
PY - 2024
DO - https://doi.org/10.1016/j.actaastro.2024.03.040
SN - 0094-5765
VL - 219
SP - 399
EP - 407
PB - Elsevier Ltd.
CY - Amsterdam, Niederlande
AN - OPUS4-60182
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arai, Marylyn Setsuko
A1 - Kim, Hyunho
A1 - Pascavis, Madeleine
A1 - Cha, Baekdong
A1 - Brambilla, Gabriel
A1 - Cho, Young Kwan
A1 - Park, Jinho
A1 - Vilela, Raquel R. C.
A1 - de Camargo, Andrea S. S.
A1 - Castro, Cesar M.
A1 - Lee, Hakho
T1 - Upconverting Nanoparticle-based Enhanced Luminescence Lateral-Flow Assay for Urinary Biomarker Monitoring
N2 - Development of efficient portable sensors for accurately detecting biomarkers is crucial for early disease diagnosis, yet remains a significant challenge. To address this need, we introduce the enhanced luminescence lateral-flow assay, which leverages highly luminescent upconverting nanoparticles (UCNPs) alongside a portable reader and a smartphone app. The sensor’s efficiency and versatility were shown for kidney health monitoring as a proof of concept. We engineered Er3+- and Tm3+-doped UCNPs coated with multiple layers, including an undoped
inert matrix shell, a mesoporous silica shell, and an outer layer of
gold (UCNP@mSiO2@Au). These coatings synergistically enhance emission by over 40-fold and facilitate biomolecule conjugation, rendering UCNP@mSiO2@Au easy to use and suitable for a broad range of bioapplications. Employing these optimized nanoparticles in lateral-flow assays, we successfully detected two acute kidney injury-related biomarkers-kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)-in urine samples. Using our sensor platform, KIM-1 and NGAL can be accurately detected and quantified
within the range of 0.1 to 20 ng/mL, boasting impressively low limits of detection at 0.28 and 0.23 ng/mL, respectively. Validating our approach, we analyzed clinical urine samples, achieving biomarker concentrations that closely correlated with results obtained via ELISA. Importantly, our system enables biomarker quantification in less than 15 min, underscoring the performance of our novel UCNP-based approach and its potential as reliable, rapid, and user-friendly diagnostics.
KW - Biosensor
KW - Upconverting nanoparticles
KW - Lateral flow
KW - Portable sensor
KW - Kidney injury
PY - 2024
DO - https://doi.org/10.1021/acsami.4c06117
SN - 1944-8244
VL - 16
IS - 29
SP - 38243
EP - 38251
PB - American Chemical Society (ACS)
AN - OPUS4-60689
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schilling, Markus
A1 - Marschall, Niklas
A1 - Niebergall, Ute
A1 - Wachtendorf, Volker
A1 - Böhning, Martin
T1 - Characteristics of environmental stress cracking of PE-HD induced by biodiesel and diesel fuels
N2 - In the context of the increasing effect of carbon dioxide emissions on the global climate biodiesel produced from renewable sources has emerged as a promising contender replacing fossil fuels, especially in long-range transport vehicles, using existing engines and infrastructure.
High-density polyethylene is one of the prevailing materials for pipe and container applications for storage and transport of such fuels, both, from fossil and renewable resources. The contact with the respective fuels raises questions concerning material compatibility as biodiesel exhibits significant differences compared to conventional diesel fuel affecting its sorption and plasticization behavior in polyethylene. In this study, its behavior with respect to environmental stress cracking, considered one of the most frequent damage mechanisms leading to failure of polymer parts and packaging, was evaluated using the well-established Full Notch Creep Test. This
approach allows for a detailed fracture surface analysis using imaging techniques, such as optical and laser scanning microscopy, as well as infrared spectroscopy. Comparing the environmental stress cracking behavior in standard surfactant solutions with that in biodiesel and diesel, respective crack propagation rates, showing different levels of acceleration, were determined and details of the underlying mechanisms could be revealed.
Furthermore, the specific infrared absorption of the biodiesel’s ester functionality allows its semi-quantitative determination on the fracture surface of the tested specimens after failure. Thus, a preferred uptake of sorptive fluids in the fracture zone due to local morphological changes of the polyethylene could be directly evidenced by infrared spectroscopy.
KW - Environmental stress cracking (ESC)
KW - Full notch creep test (FNCT)
KW - Confocal laser scanning microscopy (LSM)
KW - Biodiesel
KW - Diesel
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608591
DO - https://doi.org/10.1016/j.polymertesting.2024.108547
SN - 0142-9418
VL - 138
SP - 1
EP - 16
PB - Elsevier Ltd.
AN - OPUS4-60859
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Salari, Farid
A1 - Zocca, Andrea
A1 - Bosetti, Paolo
A1 - Hlaváček, Petr
A1 - Italiano, Antonino
A1 - Gobbin, Filippo
A1 - Colombo, Paolo
A1 - Kühne, Hans-Carsten
A1 - Sglavo, Vincenzo M.
T1 - Powder-bed 3D printing by selective activation of magnesium phosphate cement: Determining significant processing parameters and their effect on mechanical strength
N2 - The present work addresses powder bed binder jetting additive manufacturing by selective magnesium phosphate cement activation. Despite the potential of this technology to aid the digitalization of the construction industry, the effect of processing parameters on the mechanical performance of printed materials has not yet been studied to generate a guideline for the further development of the technology. Statistical methodologies were used to screen the effect of four printing process parameters (printing speed, layer thickness, raster angle, and build direction on flexural and compressive strength). As the exploited technology works with constant fluid pressure, the physical interpretation of the effect of each factor can be considered taking into account the interactions between the binder materials in the powder bed. Analysis of variance (ANOVA) indicated that printing speed and layer thickness significantly affect mechanical performances. Furthermore, the layout of samples for the printing process is preferable to be parallel the printhead movement. An anisotropic behavior was observed, and the samples subjected to compressive forces parallel to the layer plane possessed lower strength values. This effect can be interpreted as a result of a weak area of low density in between layers, leading to a pronounced delamination under compression. Even though the strength of the printed material is not suitable for a structural concrete, it can be marginally improved by design of experiment and optimized for non-structural applications, such as for porous artificial stone. Design of experiment coupled with ANOVA methods can be used in the future to support the development of novel material mixtures, thus expanding the fields of application of this novel additive manufacturing technology.
KW - Concrete 3D-printing
KW - Particle-bed binder jetting
KW - Design of experiment
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601654
DO - https://doi.org/10.1016/j.oceram.2024.100609
VL - 18
SP - 1
EP - 11
PB - Elsevier B.V.
AN - OPUS4-60165
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schilling, Markus
A1 - Niebergall, Ute
A1 - Marschall, Niklas
A1 - Meinel, Dietmar
A1 - Böhning, Martin
T1 - Relation of craze to crack length during slow crack growth phenomena in high‐density polyethylene
N2 - The craze‐crack mechanism occurring in high‐density polyethylene (HDPE) causing slow crack growth and environmental stress cracking is investigated in detail with respect to the relation of crack length and the related craze zone. This is essential for the understanding of the resulting features of the formed fracture surface and their interpretation in the context of the transition from crack propagation to ductile shear deformation. It turns out that an already formed craze zone does not inevitably result in formation of a propagating crack, but could also undergo ductile failure. For the examination, the full notch creep test (FNCT) was employed with a subsequent advanced fracture surface analysis that was performed using various imaging techniques: light microscopy, laser scanning microscopy, scanning electron microscopy, and X‐ray micro computed tomography scan. FNCT specimens were progressively damaged for increasing durations under standard test conditions applying Arkopal, the standard surfactant solution, and biodiesel as test media were used to analyze the stepwise growth of cracks and crazes. From considerations based on well‐established fracture mechanics approaches, a theoretical correlation between the length of the actual crack and the length of the preceding craze zone was established that could be evidenced and affirmed by FNCT fracture surface analysis. Moreover, the yield strength of a HDPE material exposed to a certain medium as detected by a classic tensile test was found to be the crucial value of true stress to induce the transition from crack propagation due to the craze‐crack mechanism to shear deformation during FNCT measurements.
Highlights
- Progress of crack formation in high‐density polyethylene is analyzed by different imaging techniques
- Determined growth rates depend on distinction between craze zone and crack
- The ratio of the present crack to the anteceding craze zone is validated theoretically
- The transition from crack propagation to ductile shear deformation is identified
- An already formed craze zone may still fail by ductile mechanisms
KW - Craze-crack mechanism
KW - Environmental stress cracking (ESC)
KW - Full notch creep test (FNCT)
KW - Laser scanning microscopy (LSM)
KW - Slow crack growth (SCG)
KW - X-ray computed tomography (CT)
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601831
DO - https://doi.org/10.1002/pen.26698
SN - 1548-2634
VL - 64
IS - 6
SP - 2387
EP - 2403
PB - Wiley
AN - OPUS4-60183
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gadelmeier, C.
A1 - Agudo Jácome, Leonardo
A1 - Suárez Ocano, Patricia
A1 - Glatzel, U.
T1 - Effect of stacking fault energy (SFE) of single crystal, equiatomic CrCoNi and Cantor alloy on creep resistance
N2 - Compared to mechanisms like solid solution strengthening, the stacking fault energy (SFE) should be considered as a further factor that influences the material properties. The effect of SFE of alloys or individual elements on strength and resistance can vary considerably. In the high-temperature regime above 700 ◦C, there are still significant gaps in the knowledge about the effect of the SFE on the mechanical properties of single-phase alloys. The effect of SFE on creep resistance of two face-entered cubic equiatomic medium and high entropy alloys, CrCoNi and CrMnFeCoNi, respectively, is evaluated to fill parts of these gaps. Using the Bridgman solidification process, the alloys were produced as single crystals and crept under vacuum at 700 ◦C up to 1100 ◦C. This work shows a significant impact of the lower SFE of CrCoNi on the creep behavior compared to the results of previous investigations of CrMnFeCoNi. The creep resistance of the former is higher over the complete temperature range. At very high temperatures, the strengthening effect of the stacking faults is significantly present. The formation of tetragonal stacking faults and extended dislocation nodes can be identified as the reason for this effect.
KW - Medium entropy alloy
KW - MEA
KW - HEA
KW - Single crystal
KW - CrCoNi
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-602620
DO - https://doi.org/10.1016/j.msea.2024.146779
SN - 0921-5093
VL - A 908
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-60262
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kingsbery, P.
A1 - Manzoni, Anna Maria
A1 - Suárez Ocano, Patricia
A1 - Többens, D. M.
A1 - Stephan-Scherb, C.
T1 - High‐temperature KCl‐induced corrosion of high Cr and Ni alloys investigated by in‐situ diffraction
N2 - High‐temperature KCl‐induced corrosion in laboratory air was observed in situ utilizing X‐ray diffraction. High Cr‐containing model alloys (Fe‐13Cr, Fe‐18Cr‐12Ni, and Fe‐25Cr‐20Ni) were coated with KCl and exposed to dry air at 560°C. KCl‐free alloys were studied in the equivalent atmosphere as a reference. After exposure to KCl‐free environments, all alloys showed the formation of very thin oxide layers, indicating good corrosion resistance. In contrast, KCl‐bearing alloys showed distinct damage after exposure.
KW - Corrosion
KW - In-situ diffraction
KW - High-temperature corrosion
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600831
DO - https://doi.org/10.1002/maco.202314224
SN - 0947-5117
SP - 1
EP - 10
PB - Wiley VHC-Verlag
AN - OPUS4-60083
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Feng, Wen
A1 - Gemming, Thomas
A1 - Giebeler, Lars
A1 - Qu, Jiang
A1 - Weinel, Kristina
A1 - Agudo Jácome, Leonardo
A1 - Büchner, Bernd
A1 - González-Martínez, Ignacio
T1 - Influence of magnetic field on electron beam-induced Coulomb explosion of gold microparticles in transmission electron microscopy
N2 - In this work we instigated the fragmentation of Au microparticles supported on a thin amorphous carbon film by irradiating them with a gradually convergent electron beam inside the Transmission Electron Microscope. This phenomenon has been generically labeled as “electron beam-induced fragmentation” or EBIF and its physical origin remains contested. On the one hand, EBIF has been primarily characterized as a consequence of beam-induced heating. On the other, EBIF has been attributed to beam-induced charging eventually leading to Coulomb explosion. To test the feasibility of the charging framework for EBIF, we instigated the fragmentation of Au particles under two different experimental conditions. First, with the magnetic objective lens of the microscope operating at full capacity, i.e. background magnetic field B = 2 T, and with the magnetic objective lens switched off (Lorenz mode), i.e. B = 0 T. We observe that the presence or absence of the magnetic field noticeably affects the critical current density at which EBIF occurs. This strongly suggests that magnetic field effects play a crucial role in instigating EBIF on the microparticles. The dependence of the value of the critical current density on the absence or presence of an ambient magnetic field cannot be accounted for by the beam-induced heating model. Consequently, this work presents robust experimental evidence suggesting that Coulomb explosion driven by electrostatic charging is the root cause of EBIF.
KW - Electron beam-induced fragmentation
KW - Coulomb explosion
KW - X-ray diffraction
KW - Lorenz transmission electron microscopy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600247
DO - https://doi.org/10.1016/j.ultramic.2024.113978
SN - 1879-2723
VL - 262
SP - 1
EP - 8
PB - Elsevier
CY - Amsterdam
AN - OPUS4-60024
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Blaeß, Carsten
A1 - Müller, Ralf
T1 - Viscous crack healing in soda–lime–magnesium–silicate–ZrO2 glass matrix composites
N2 - AbstractThe present study investigates the influence of the crystal volume content on viscous crack healing in glass ceramic glass sealants. To ensure constant microstructure during healing, soda–lime–magnesium silicate glass matrix composites with varied volume fractions of ZrO2 filler particles were used. Crack healing was studied on radial cracks induced by Vickers indentation, which were stepwise annealed to monitor the healing progress by confocal laser scanning microscopy. Confirming previous studies, healing of radial cracks in pure glass was found delayed by global flow phenomena like crack widening and crack edge and tip rounding to minimize the sample surface. With increasing ZrO2 filler content, these global flow phenomena were progressively inhibited whereas local flow phenomena like sharp crack tip healing could still occur. As a result, crack healing was even accelerated by filler particles up to a maximum filler content of 17 vol% whereas crack healing was fully suppressed only at 33 vol% filler content.
KW - Crack healing
KW - Glass matrix composite
KW - Solid oxide fuell cell
KW - Vickers identation
KW - Viscosity
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607860
DO - https://doi.org/10.1111/jace.20002
SN - 0002-7820
SP - 1
EP - 12
PB - Wiley
AN - OPUS4-60786
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stargardt, Patrick
A1 - Bresch, Sophie
A1 - Falkenberg, Rainer
A1 - Mieller, Björn
T1 - Effect of Reaction Layers on Internal Stresses in Co‐Fired Multilayers of Calcium Manganate and Calcium Cobaltite
N2 - A widespread recovery of waste heat requires a cost‐effective production of thermoelectric generators. Thermoelectric oxides are predestined for use at high temperatures. For manufacturing reasons, a multilayer generator design will be easily scalable and cost‐effective. To evaluate the potential of ceramic multilayer technology for that purpose, a multilayer of the promising thermoelectric oxides calcium cobaltite (Ca3Co4O9), calcium manganate (CMO, CaMnO3), and glass–ceramic insulation layers is fabricated. Cracks and reaction layers at the interfaces are observed in the microstructure. The compositions of these reaction layers are identified by energy‐dispersive X‐ray spectroscopy and X‐ray diffraction. Mechanical and thermal properties of all layers are compiled from literature or determined by purposeful sample preparation and testing. Based on this data set, the internal stresses in the multilayer after co‐firing are calculated numerically. It is shown that tensile stresses in the range of 50 MPa occur in the CMO layers. The reaction layers have only a minor influence on the level of these residual stresses. Herein, it is proven that the material system is basically suitable for multilayer generator production, but that the co‐firing process and the layer structure must be adapted to improve densification and reduce the tensile stresses in the CMO.
KW - Ceramic multilayers
KW - Co-firings
KW - Internal stresses
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601626
DO - https://doi.org/10.1002/pssa.202300956
SP - 1
EP - 9
PB - Wiley VHC-Verlag
AN - OPUS4-60162
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zocca, Andrea
A1 - Günster, Jens
T1 - Towards a debinding-free additive manufacturing of ceramics: A development perspective of water-based LSD and LIS technologies
N2 - Ceramic additive manufacturing (AM) requires a complex process chain with various post-processing steps that require expensive machines and special expertise. The key to further market penetration is AM that makes it possible to integrate into an already established ceramic process chain. Most successful AM technologies for ceramics are, however, based on processes that initially have been developed for polymeric materials. For ceramics AM, polymers or precursors are loaded with ceramic particles. This strategy facilitates the entry into AM, however the introduction of organic additives into the ceramic process chain represents a considerable technological challenge to ultimately obtain a ceramic component after additive shaping. In the present communication, two technologies based on ceramic suspensions will be introduced, the “layerwise slurry deposition” (LSD) and “laser induced slip casting” (LIS) technology. Both technologies take advantage of the high packing densities reached by conventional slip casting and moreover enable the processing of fines, even nanoparticles.
KW - Additive Manufacturing
KW - Ceramic
KW - Water-based
KW - Debinding
KW - Slurry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605531
DO - https://doi.org/10.1016/j.oceram.2024.100632
SN - 2666-5395
VL - 19
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-60553
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoffmann, Moritz
A1 - Stawarczyk, Bogna
A1 - Günster, Jens
A1 - Zocca, Andrea
T1 - Influence of additives and binder on the physical properties of dental silicate glass-ceramic feedstock for additive manufacturing
N2 - Objectives
The aim of the study was to investigate the impact of organic additives (binder, plasticizer, and the cross-linking ink) in the formulation of water-based feedstocks on the properties of a dental feldspathic glass-ceramic material developed for the slurry-based additive manufacturing technology “LSD-print.”
Material and methods
Three water-based feldspathic feedstocks were produced to study the effects of polyvinyl alcohol (AC1) and poly (sodium 4-styrenesulfonate) (AC2) as binder systems. A feedstock without organic additives was tested as the control group (CG). Disc-shaped (n = 15) and bar (n = 7) specimens were slip-cast and characterized in the green and fired states. In the green state, density and flexural strength were measured. In the fired state, density, shrinkage, flexural strength (FS), Weibull modulus, fracture toughness (KIC), Martens parameters, and microstructure were analyzed. Disc-shaped and bar specimens were also cut from commercially available CAD/CAM blocks and used as a target reference (TR) for the fired state.
Results
In the green state, CG showed the highest bulk density but the lowest FS, while the highest FS in the green state was achieved with the addition of a cross-linking ink. After firing, no significant differences in density and a similar microstructure were observed for all slip-cast groups, indicating that almost complete densification could be achieved. The CAD/CAM specimens showed the highest mean FS, Weibull modulus, and KIC, with significant differences between some of the slip-cast groups.
Significance
These results suggest that the investigated feedstocks are promising candidates for the slurry-based additive manufacturing of restorations meeting the class 1a requirements according to DIN EN ISO 6871:2019–01.
KW - Firing
KW - 3D-printing
KW - Silicate glass-ceramics
KW - Debinding
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600516
DO - https://doi.org/10.1016/j.jmbbm.2024.106563
SN - 1751-6161
VL - 155
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-60051
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sänger, Johanna
A1 - König, N.F.
A1 - De Marzi, A.
A1 - Zocca, Andrea
A1 - Franchin, G.
A1 - Bermejo, R.
A1 - Colombo, P.
A1 - Günster, Jens
T1 - Linear volumetric additive manufacturing of zirconia from a transparent photopolymerizable ceramic slurry via Xolography
N2 - Advanced ceramics printed with photon-based additive manufacturing deals with anisotropic mechanical properties from the layer-by-layer manufacturing. Motivated by the success in using highly filled transparent slurries containing nanoparticles for powder-based two-photon-polymerization (2PP) for advanced ceramic printing, this works approach is the transfer to Xolography, a volumetric additive manufacturing technology based on linear two-photon excitation and without recoating steps. This paper reports the results of a preliminary investigation optimizing the photocurable slurry to the requirements of Xolography in terms of transparency, over a significantly larger mean free path, compared to 2PP. A feedstock filled with 70 % weight fraction of ceramic particles (∼30 vol%) exhibiting an exceptionally high degree of transparency in the relevant wavelength range of 400–800 nm was prepared from 5 nm zirconia nanoparticles. The high transparency of the photocurable slurry is attributed to the near-monomodal particle size distribution of the zirconia nanoparticles used.
KW - Additive manufacturing
KW - Xolography
KW - Ceramic
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608908
DO - https://doi.org/10.1016/j.oceram.2024.100655
SN - 2666-5395
VL - 19
SP - 1
EP - 9
PB - Elsevier BV
AN - OPUS4-60890
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Waitelonis, Jörg
A1 - Birkholz, Henk
A1 - Jung, Matthias
A1 - Schilling, Markus
A1 - v. Hartrott, Philipp
A1 - Bruns, Marian
A1 - Schaarschmidt, Jörg
A1 - Beilke, Kristian
A1 - Mutz, Marcel
A1 - Nebel, Vincent
A1 - Königer, Veit
A1 - Beran, Lisa
A1 - Kraus, Tobias
A1 - Vyas, Akhilesh
A1 - Vogt, Lars
A1 - Blum, Moritz
A1 - Ell, Basil
A1 - Chen, Ya‐Fan
A1 - Waurischk, Tina
A1 - Thomas, Akhil
A1 - Durmaz, Ali Riza
A1 - Ben Hassine, Sahar
A1 - Fresemann, Carina
A1 - Dziwis, Gordian
A1 - Beygi Nasrabadi, Hossein
A1 - Hanke, Thomas
A1 - Telong, Melissa
A1 - Pirskawetz, Stephan
A1 - Kamal, Mohamed
A1 - Bjarsch, Thomas
A1 - Pähler, Ursula
A1 - Hofmann, Peter
A1 - Leemhuis, Mena
A1 - Özçep, Özgür L.
A1 - Meyer, Lars‐Peter
A1 - Skrotzki, Birgit
A1 - Neugebauer, Jörg
A1 - Wenzel, Wolfgang
A1 - Sack, Harald
A1 - Eberl, Chris
A1 - Portella, Pedro Dolabella
A1 - Hickel, Tilmann
A1 - Mädler, Lutz
A1 - Gumbsch, Peter
T1 - Concepts for a Semantically Accessible Materials Data Space: Overview over Specific Implementations in Materials Science
N2 - This article describes advancements in the ongoing digital transformation in materials science and engineering. It is driven by domain‐specific successes and the development of specialized digital data spaces. There is an evident and increasing need for standardization across various subdomains to support science data exchange across entities. The MaterialDigital Initiative, funded by the German Federal Ministry of Education and Research, takes on a key role in this context, fostering collaborative efforts to establish a unified materials data space. The implementation of digital workflows and Semantic Web technologies, such as ontologies and knowledge graphs, facilitates the semantic integration of heterogeneous data and tools at multiple scales. Central to this effort is the prototyping of a knowledge graph that employs application ontologies tailored to specific data domains, thereby enhancing semantic interoperability. The collaborative approach of the Initiative's community provides significant support infrastructure for understanding and implementing standardized data structures, enhancing the efficiency of data‐driven processes in materials development and discovery. Insights and methodologies developed via the MaterialDigital Initiative emphasize the transformative potential of ontology‐based approaches in materials science, paving the way toward simplified integration into a unified, consolidated data space of high value.
KW - Semantic Interoperability
KW - Data Spaces
KW - Integration Workflows
KW - MaterialDigital
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622952
DO - https://doi.org/10.1002/adem.202401092
SN - 1527-2648
SP - 1
EP - 25
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-62295
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Riechers, Birte
A1 - Das, Amlan
A1 - Rashidi, Reza
A1 - Dufresne, Eric
A1 - Maaß, Robert
T1 - Metallic glasses: Elastically stiff yet flowing at any stress
N2 - Crystalline solids have a minimum stress needed to displace atoms or to move defects. This stress defines the true elastic limit and is generally a sizeable share of the macroscopic yield stress. Here we demonstrate that a metallic glass, an amorphous solid with a yield stress in the giga-pascal regime, lacks such a true microscopic elastic limit. Leveraging in-situ coherent x-ray scattering, we uncover a strongly accelerated atomic-scale transport upon the application of a stress as small as 0.005 times the yield stress. With increasing stress levels, the distribution of structural relaxation times changes from compressed exponential to simple exponential form, revealing a stress–temperature equivalence in the time-scale domain. These findings strongly promote a microstructurally heterogeneous picture of metallic glasses, in which a part of the amorphous microstructure controls macroscopic yielding whereas another part admits microplastic flow at any stress.
KW - Metallic glasses
KW - Microstructure
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624530
DO - https://doi.org/10.1016/j.mattod.2024.11.015
VL - 82
SP - 92
EP - 98
PB - Elsevier B.V.
AN - OPUS4-62453
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fareed, Adnan
A1 - Rosalie, Julian
A1 - Kar, Satyakam
A1 - Fähler, Sebastian
A1 - Maaß, Robert
T1 - Small-scale functional fatigue of a Ni-Mn-Ga Heusler alloy
N2 - Functional fatigue of shape-memory alloys is a considerable threat to the reliable service of actuation devices. Here, we demonstrate the essentially degradation-free cyclic phase-transformation behavior of Ni-Mn-Ga microcrystals up to one million stress-driven superelastic cycles. Cyclic dissipation amounts to about 1/5 of the bulk counterpart and remains unaffected during cycling, even after the introduction of dislocation structures via plastic straining. Plastic yielding and the transformation stress largely exceed the known bulk values. However, the transformation-stress is found to depend on plastic pre-straining, which suggests that the size-affected transformation stress is sensitive to the initial defect structure and that it can be tuned by a targeted introduction of dislocations. These findings demonstrate the high suitability of Ni-Mn-Ga as a robust shape-memory alloy in small-scale functional device engineering.
KW - Superelasticity
KW - Shape-memory alloys
KW - Functional fatigue
KW - Ni-Mn-Ga
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600695
DO - https://doi.org/10.1016/j.actamat.2024.119988
VL - 274
SP - 1
EP - 10
PB - Elsevier B.V.
AN - OPUS4-60069
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Riechers, Birte
A1 - Das, Amlan
A1 - Dufresne, Eric
A1 - Derlet, Peter M.
A1 - Maaß, Robert
T1 - Intermittent cluster dynamics and temporal fractional diffusion in a bulk metallic glass
N2 - Glassy solids evolve towards lower-energy structural states by physical aging. This can be characterized by structural relaxation times, the assessment of which is essential for understanding the glass’ time-dependent property changes. Conducted over short times, a continuous increase of relaxation times with time is seen, suggesting a time-dependent dissipative transport mechanism. By focusing on micro-structural rearrangements at the atomic-scale, we demonstrate the emergence of sub-diffusive anomalous transport and therefore temporal fractional diffusion in a metallic glass, which we track via coherent x-ray scattering conducted over more than 300,000 s. At the longest probed decorrelation times, a transition from classical stretched exponential to a power-law behavior occurs, which in concert with atomistic simulations reveals collective and intermittent atomic motion. Our observations give a physical basis for classical stretched exponential relaxation behavior, uncover a new power-law governed collective transport regime for metallic glasses at long and practically relevant time-scales, and demonstrate a rich and highly non-monotonous aging response in a glassy solid, thereby challenging the common framework of homogeneous aging and atomic scale diffusion.
KW - Glassy solids
KW - Fractional diffusion
KW - Coherent x-ray scattering
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608015
DO - https://doi.org/10.1038/s41467-024-50758-3
VL - 15
IS - 1
SP - 1
EP - 9
PB - Springer Science and Business Media LLC
AN - OPUS4-60801
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wang, Zengquan
A1 - Riechers, Birte
A1 - Derlet, Peter M.
A1 - Maaß, Robert
T1 - Atomic cluster dynamics causes intermittent aging of metallic glasses
N2 - In the past two decades, numerous relaxation or physical aging experiments of metallic glasses have revealed signatures of intermittent atomic-scale processes. Revealed via intensity cross-correlations from coherent scattering using X-ray photon correlation spectroscopy (XPCS), the observed abrupt changes in the time-domain of atomic motion does not fit the picture of gradual slowing down of relaxation times and their origin continues to remain unclear. Using a binary Lennard-Jones model glass subjected to microsecond-long isotherms, we show here that temporally and spatially heterogeneous atomic-cluster activity at different length-scales drive the emergence of highly non-monotonous intensity cross-correlations. The simulated XPCS experiments reveal a variety of time-dependent intensity-cross correlations that, depending on both the structural evolution and the 𝑞-space sampling, give detailed insights into the possible structural origins of intermittent aging measured with XPCS.
KW - Metallic glasses
KW - Aging
KW - Molecular dynamics
KW - XPCS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595415
DO - https://doi.org/10.1016/j.actamat.2024.119730
SN - 1359-6454
VL - 267
SP - 1
EP - 9
PB - Elsevier B.V.
CY - Amsterdam, Niederlande
AN - OPUS4-59541
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fantin, Andrea
A1 - Manzoni, Anna Maria
A1 - Springer, H.
A1 - Darvishi Kamachali, Reza
A1 - Maaß, Robert
T1 - Local lattice distortions and chemical short-range order in MoNbTaW
N2 - Extended X-ray absorption fine structure (EXAFS) conducted on an equiatomic MoNbTaW bcc medium-entropy alloy that was annealed at 2273 K reveals unexpectedly small 1st and 2nd shell element-specific lattice distortions. An experimental size-mismatch parameter, δexp, is determined to be ca. 50% lower than the corresponding calculated value. Around W, short-range order (SRO) preferring 4d elements in the 1st and 2nd shells persists. A Nb-W ordering is found, which is reminiscent of ordering emerging at lower temperatures in the B2(Mo,W;Ta,Nb)- and B32(Nb,W)-phases. With high-temperature ordering preferences in fcc also foreshadowing low-temperature phase, these findings suggest a general feature of high-temperature SRO.
KW - High Entropy Alloys
KW - Short-range order
KW - Lattice distortions
KW - EXAFS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598164
DO - https://doi.org/10.1080/21663831.2024.2326014
SN - 2166-3831
VL - 12
IS - 5
SP - 346
EP - 354
PB - Taylor & Francis
AN - OPUS4-59816
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lanzino, Maria Carolina
A1 - Le, Long-Quan R. V.
A1 - Wilbig, Janka
A1 - Rheinheimer, Wolfgang
A1 - Seidenstuecker, Michael
A1 - Günster, Jens
A1 - Killinger, Andreas
T1 - Thin GB14 coatings on implants using HVSFS
N2 - Enhancing osseointegration, the process by which medical implants securely bond to bone, is crucial for improving patient outcomes in orthopedics and dental surgery. Calcium alkali orthophosphates, with their superior bioactivity, resorbability, and chemical resemblance to bone minerals, have emerged as promising candidates for implant coatings. These materials offer improved solubility and lower melting points due to the substitution of calcium with potassium and sodium, along with the addition of magnesium oxide. This study investigates GB14 calcium alkali orthophosphate coatings applied via High Velocity Suspension Flame Spraying (HVSFS), a technique that enables precise control over coating properties. A porosity target of >10% was set to promote bone growth, and we achieved porosities up to 13%, ensuring better cell penetration and stability at the implant-bone interface. Coatings were produced using different gas parameters and distances, with their microstructure and phase composition analyzed using scanning electron microscope (SEM), Vickers hardness testing and X-ray diffraction (XRD). Additionally, roughness and porosity were also assessed. Different coating’s microstructures were achieved by varying stand-off distance and gas parameters. Increasing stand-off distance while reducing gas stoichiometry enabled the production of calcium alkali orthophosphate coatings with fewer cracks, higher porosity and a hardness level comparable to that of state-of-the-art tricalcium phosphate (TCP) coatings. The sample with optimized properties in terms of achieved microstructure and topography was selected for in vitro testing using MG63 osteosarcoma cells to evaluate cell proliferation and adhesion. WST (I) assay, LDH assay, and live/dead staining confirmed the biocompatibility of the coatings, highlighting the potential of HVSFS to enhance osseointegration and outperform conventional methods in implantology. No relevant cytotoxicity could be shown and cells show a good proliferation over time. These results highlight thus the potential of HVSFS to produce thin, bioactive and resorbable coatings to enhance osseointegration.
KW - Bio ceramics
KW - Spray coating
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623983
DO - https://doi.org/10.3389/fmats.2024.1522447
SN - 2296-8016
VL - 11
IS - 1522447
SP - 1
EP - 14
PB - Frontiers Media SA
AN - OPUS4-62398
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sänger, Johanna C.
A1 - Riechers, Birte
A1 - Pauw, Brian Richard
A1 - Maaß, Robert
A1 - Günster, Jens
T1 - Microplastic response of 2PP‐printed ceramics
N2 - AbstractTwo‐photon polymerization (2PP) additive manufacturing (AM) utilizes feedstocks of ceramic nanoparticles of a few nanometers in diameter, enabling the fabrication of highly accurate technical ceramic design with structural details as small as 500 nm. The performance of these materials is expected to differ from conventional AM ceramics, as nanoparticles and three‐dimensional printing at high resolution introduce new microstructural aspects. This study applies 2PP‐AM of yttria‐stabilized zirconia to investigate the mechanical response behavior under compressive load, probing the influence of smallest structural units induced by the line packing during the printing process, design of sintered microblocks, and sintering temperature and thereby microstructure. We find a dissipative mechanical response enhanced by sintering at lower temperatures than conventional. The pursued 2PP‐AM approach yields a microstructured material with an increased number of grain boundaries that proposedly play a major role in facilitating energy dissipation within the here printed ceramic material. This microplastic response is further triggered by the filigree structures induced by hollow line packing at the order of the critical defect size of ceramics. Together, these unique aspects made accessible by the 2PP‐AM approach contribute to a heterogeneous nano‐ and microstructure, and hint toward opportunities for tailoring the mechanical response in future ceramic applications.
KW - Manufacturing
KW - Mechanical properties
KW - Microstructure
KW - Plasticity
KW - Zirconia: yttria stabilized
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605176
DO - https://doi.org/10.1111/jace.19849
SN - 1551-2916
VL - 107
IS - 10
SP - 6636
EP - 6645
PB - Wiley
CY - Oxford
AN - OPUS4-60517
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jacobson, David
A1 - Darvishi Kamachali, Reza
A1 - Thompson, Gregory
T1 - Coupling density phase field models with atomistic potentials
N2 - A density-based phase field model is developed where the free energy functional is explicitly linked with molecular dynamics and is referred to as the Molecular Phase Field Method (MoPF). MoPF simulations involve expressing interatomic potentials in terms of density to form a density based free energy functional. Inputs to this functional are taken from atomistics such that the phase field density profile matches the corresponding density profile from atomistic simulations. We analyze our results by comparing the MoPF calculated excess interfacial energies with excess interfacial energies calculated using molecular dynamics associated with several nickel grain boundaries. Additionally, a comparison is made between our results and the interfacial energies of a \Sigma7 boundary across a variety of FCC systems simulated using density functional theory. The MoPF method is able to successfully predict grain boundary free energy trends between grain boundary and material types offering an atomistically informed mesoscale formulation for studying grain boundary physics.
KW - Density-based Phase-Field Modelling
KW - Atomistic Simulation
KW - Grain Boundary
PY - 2024
DO - https://doi.org/10.1016/j.commatsci.2023.112763
VL - 233
SP - 1
EP - 6
PB - Elsevier
AN - OPUS4-59360
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dzugan, J.
A1 - Lucon, E.
A1 - Koukolikova, M.
A1 - Li, Y.
A1 - Rzepa, S.
A1 - Yasin, M.S.
A1 - Shao, S.
A1 - Shamsaei, N.
A1 - Seifi, M.
A1 - Lodeiro, M.
A1 - Lefebvre, F.
A1 - Mayer, U.
A1 - Olbricht, Jürgen
A1 - Houska, M.
A1 - Mentl, V.
A1 - You, Z.
T1 - ASTM interlaboratory study on tensile testing of AM deposited and wrought steel using miniature specimens
N2 - An interlaboratory study, involving eigth international laboratories and coordinated by COMTES FHT (Czech Republic), was conducted to validate tensile measurements obtained using miniature specimens on additively manufactured (AM) components and artifacts. In addition to AM 316L stainless steel (316L SS), a wrought highstrength steel (34CrNiMo6V, equivalent to AISI 4340) was also used. Based on the results, a precision statement in accordance with ASTM E691 standard practice was developed, intended for inclusion in a proposed annex to the ASTM E8/E8M tension testing method. The primary outcomes of the study highlighted the agreement between yield and tensile strength measured from miniature and standard-sized tensile specimens. Furthermore, most tensile properties exhibited similar standard deviations, offering users insight into the efficacy of miniature specimen applications.
KW - 316L stainless steel
KW - Additive manufacturing
KW - High-strength steel
KW - Miniature specimens
KW - Tensile tests
PY - 2024
DO - https://doi.org/10.1016/j.tafmec.2024.104410
SN - 0167-8442
VL - 131
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-60180
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Darvishi Kamachali, Reza
A1 - Wallis, Theophilus
A1 - Ikeda, Yuki
A1 - Saikia, U.
A1 - Ahmadian, A.
A1 - Liebscher, C.
A1 - Hickel, Tilmann
A1 - Maaß, Robert
T1 - Giant segregation transition as origin of liquid metal embrittlement in the Fe-Zn system
N2 - A giant Zn segregation transition is revealed using CALPHAD-integrated density-based modeling of segregation into Fe grain boundaries (GBs). The results show that above a threshold of only a few atomic percent Zn in the alloy, a substantial amount of up to 60 at.% Zn can segregate to the GB. We found that the amount of segregation abruptly increases with decreasing temperature, while the Zn content in the alloy required for triggering the segregation transition decreases. Direct evidence of the Zn segregation transition is obtained using high-resolution scanning transmission electron microscopy. Base on the model, we trace the origin of the segregation transition back to the low cohesive energy of Zn and a miscibility gap in Fe-Zn GB, arising from the magnetic ordering effect, which is confirmed by ab-initio calculations. We also show that the massive Zn segregation resulting from the segregation transition greatly assists with liquid wetting and reduces the work of separation along the GB. The current predictions suggest that control over Zn segregation, by both alloy design and optimizing the galvanization and welding processes, may offer preventive strategies against liquid metal embrittlement.
KW - CALPHAD
KW - Microstructure Design
KW - Grain boundary engineering
KW - Steels
KW - Density-based Model
KW - Segregation Engineering
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584292
DO - https://doi.org/10.1016/j.scriptamat.2023.115758
SN - 1359-6462
SN - 1872-8456
VL - 238
SP - 1
EP - 5
PB - Elsevier
CY - Amsterdam
AN - OPUS4-58429
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kar, Satyakam
A1 - Ikeda, Yuki
A1 - Nielsch, Kornelius
A1 - Reith, Heiko
A1 - Maaß, Robert
A1 - Fähler, Sebastian
T1 - Multiferroic Microstructure Created from Invariant Line Constraint
N2 - Ferroic materials enable a multitude of emerging applications, and optimum functional properties are achieved when ferromagnetic and ferroelectric properties are coupled to a first‐order ferroelastic transition. In bulk materials, this first‐order transition involves an invariant habit plane, connecting coexisting phases: austenite and martensite. Theory predicts that this plane should converge to a line in thin films, but experimental evidence is missing. Here, the martensitic and magnetic microstructure of a freestanding epitaxial magnetic shape memory film is analyzed. It is shown that the martensite microstructure is determined by an invariant line constraint using lattice parameters of both phases as the only input. This line constraint explains most of the observable features, which differ fundamentally from bulk and constrained films. Furthermore, this finite‐size effect creates a remarkable checkerboard magnetic domain pattern through multiferroic coupling. The findings highlight the decisive role of finite‐size effects in multiferroics.
KW - Epitaxial films
KW - Finite-size effects
KW - Multiferroics
KW - Martensite
KW - Magnetic shape memory alloys
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637910
DO - https://doi.org/10.1002/adfm.202416638
SN - 1616-301X
VL - 35
IS - 10
SP - 1
EP - 11
PB - Wiley
AN - OPUS4-63791
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beygi Nasrabadi, Hossein
A1 - Bauer, Felix
A1 - Uhlemann, Patrick
A1 - Thärig, Steffen
A1 - Rehmer, Birgit
A1 - Skrotzki, Birgit
T1 - Mechanical testing dataset of cast copper alloys for the purpose of digitalization
N2 - This data article presents a set of primary, analyzed, and digitalized mechanical testing datasets for nine copper alloys. The mechanical testing methods including the Brinell and Vickers hardness, tensile, stress relaxation, and low-cycle fatigue (LCF) testing were performed according to the DIN/ISO standards. The obtained primary testing data (84 files) mainly contain the raw measured data along with the testing metadata of the processes, materials, and testing machines. Five secondary datasets were also provided for each testing method by collecting the main meta- and measurement data from the primary data and the outputs of data analyses. These datasets give materials scientists beneficial data for comparative material selection analyses by clarifying the wide range of mechanical properties of copper alloys, including Brinell and Vickers hardness, yield and tensile strengths, elongation, reduction of area, relaxed and residual stresses, and LCF fatigue life. Furthermore, both the primary and secondary datasets were digitalized by the approach introduced in the research article entitled “Toward a digital materials mechanical testing lab” [1]. The resulting open-linked data are the machine-processable semantic descriptions of data and their generation processes and can be easily queried by semantic searches to enable advanced data-driven materials research.
KW - FAIR principles
KW - Hardness
KW - Low-Cycle Fatigue (LCF)
KW - Tensile testing
KW - Stress relaxation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605005
DO - https://doi.org/10.1016/j.dib.2024.110687
SN - 2352-3409
SP - 1
EP - 15
PB - Elsevier BV
AN - OPUS4-60500
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jentzsch, Stefan
A1 - Stock, Daniel
A1 - Häcker, Ralf
A1 - Skrotzki, Birgit
A1 - Darvishi Kamachali, Reza
A1 - Klingbeil, Dietmar
A1 - Kindrachuk, Vitaliy
T1 - Shear Band Formation with Split Hopkinson Bar Experiments
N2 - The essence of dynamic failure is closely linked to dramatic shear deformations which often lead to the formation of adiabatic shear bands (ASB). Under high loading velocities and the subsequent rapid temperature increase, the localization of shear strain is crucial in view of safety issues of systems in mechanical and aircraft engineering, especially with respect to fast rotating components and diverse crash scenarios. In this research, we perform high speed impact tests at the split Hopkinson pressure bar (SHPB) setup and use particular hat-shaped specimen geometries that resemble the stresses and failure conditions at the component level.
In the first step, we specify a notched specimen geometry using finite element (FE) simulations to ensure pure shear. Further, quasi-static compressive tests and a series of impact tests at high strain rates of 10^3-10^4 s^-1 are conducted on specimens manufactured from a fine-grain structural steel with the properties of S355. Optical microscopy and electron backscatter diffraction (EBSD) of the sheared zones unveil significant localization to maximal shear strains of about 0.9 accompanied by grain refinement by factors 5 to 14. The displacements across the surface of the specimens are captured with subset-based local digital image correlation (DIC) during the impact time, and serve as an objective to validate a viscoplastic constitutive relationship. More precisely, the deformation distribution is accurately reproduced by the widely recognized Johnson-Cook (JC) model, which features an enhanced description of damage evolution. Thus, combining experimental and characterization techniques, continuum mechanics and reasonable optimization strategies for the identification of model parameters provides an efficient approach for comprehensive insights into the strain localization behaviour and its impact on the mechanical performance of S355 under extreme strain rates and deformations.
KW - Adiabatic shear bands
KW - Finite element analysis
KW - Viscoplastic material modelling
KW - Split Hopkinson pressure bar
KW - Hat-shaped specimen
KW - Johnson–Cook parameter identification
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613339
DO - https://doi.org/10.1016/j.ijmecsci.2024.109749
VL - 284
SP - 1
EP - 14
PB - Elsevier BV
AN - OPUS4-61333
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schilling, Markus
A1 - Bayerlein, Bernd
A1 - von Hartrott, Philipp
A1 - Waitelonis, Jörg
A1 - Birkholz, Henk
A1 - Portella, Pedro Dolabella
A1 - Skrotzki, Birgit
T1 - FAIR and Structured Data: A Domain Ontology Aligned with Standard‐Compliant Tensile Testing
N2 - The digitalization of materials science and engineering (MSE) is currently leading to remarkable advancements in materials research, design, and optimization, fueled by computer‐driven simulations, artificial intelligence, and machine learning. While these developments promise to accelerate materials innovation, challenges in quality assurance, data interoperability, and data management have to be addressed. In response, the adoption of semantic web technologies has emerged as a powerful solution in MSE. Ontologies provide structured and machine‐actionable knowledge representations that enable data integration, harmonization, and improved research collaboration. This study focuses on the tensile test ontology (TTO), which semantically represents the mechanical tensile test method and is developed within the project Plattform MaterialDigital (PMD) in connection with the PMD Core Ontology. Based on ISO 6892‐1, the test standard‐compliant TTO offers a structured vocabulary for tensile test data, ensuring data interoperability, transparency, and reproducibility. By categorizing measurement data and metadata, it facilitates comprehensive data analysis, interpretation, and systematic search in databases. The path from developing an ontology in accordance with an associated test standard, converting selected tensile test data into the interoperable resource description framework format, up to connecting the ontology and data is presented. Such a semantic connection using a data mapping procedure leads to an enhanced ability of querying. The TTO provides a valuable resource for materials researchers and engineers, promoting data and metadata standardization and sharing. Its usage ensures the generation of finable, accessible, interoperable, and reusable data while maintaining both human and machine actionability.
KW - Data Interoperability
KW - Domain Ontology Development
KW - FAIR Data Management
KW - Knowledge Representation
KW - Tensile Test Ontology
KW - Semantic Web Technologies
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598142
DO - https://doi.org/10.1002/adem.202400138
SN - 1438-1656
SP - 1
EP - 19
PB - Wiley VHC-Verlag
AN - OPUS4-59814
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhadeliya, Ashok
A1 - Rehmer, Birgit
A1 - Fedelich, Bernard
A1 - Jokisch, T.
A1 - Skrotzki, Birgit
A1 - Olbricht, Jürgen
T1 - Fatigue and fracture in dual-material specimens of nickel-based alloys fabricated by hybrid additive manufacturing
N2 - The integration of additive manufacturing with traditional processes, termed hybrid additive manufacturing, has expanded its application domain, particularly in the repair of gas turbine blade tips. However, process-related defects in additively manufactured materials, interface formation, and material property mismatches in dual-material structures can significantly impact the fatigue performance of components. This investigation examines the low cycle fatigue and fatigue crack growth behaviors in dual-material specimens of nickel-based alloys, specifically the additively manufactured STAL15 and the cast alloy 247DS, at elevated temperatures. Low cycle fatigue experiments were conducted at temperatures of 950 °C and 1000 °C under a range of strain levels (0.3%–0.8%) and fatigue crack growth tests were conducted at 950 °C with stress ratios of 0.1 and −1. Fractographic and microscopic analyses were performed to comprehend fatigue crack initiation and crack growth mechanisms in the dual-material structure. The results consistently indicated crack initiation and fatigue fracture in the additively manufactured STAL15 material. Notably, fatigue crack growth retardation was observed near the interface when the crack extended from the additively manufactured STAL15 material to the perpendicularly positioned interface. This study highlights the importance of considering yield strength mismatch, as well as the potential effects of residual stresses and grain structure differences, in the interpretation of fatigue crack growth behavior at the interface.
KW - Hybrid additive manufacturing
KW - Dual-material nickel-based alloys
KW - High-temperature fatigue crack growth
KW - Low cycle fatigue
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609340
DO - https://doi.org/10.1016/j.jmrt.2024.08.211
SN - 2238-7854
VL - 32
SP - 3737
EP - 3749
PB - Elsevier B.V.
AN - OPUS4-60934
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beygi Nasrabadi, Hossein
A1 - Norouzi, Ebrahim
A1 - Sack, Harald
A1 - Skrotzki, Birgit
T1 - Performance Evaluation of Upper‐Level Ontologies in Developing Materials Science Ontologies and Knowledge Graphs
N2 - This study tackles a significant challenge in ontology development for materials science: selecting the most appropriate upper‐level ontologies for creating application‐level ontologies and knowledge graphs. Focusing on the use case of Brinell hardness testing, the research assesses the performance of various top‐level ontologies (TLOs)—basic formal ontology (BFO), elementary multiperspective material ontology (EMMO), and provenance ontology (PROVO)—in developing Brinell testing ontologies (BTOs). Consequently, three versions of BTOs are created using combinations of these TLOs along with their integrated mid‐ and domain‐level ontologies. The performance of these ontologies is evaluated based on ten parameters: semantic richness, domain coverage, extensibility, complexity, mapping efficiency, query efficiency, integration with other ontologies, adaptability to different data contexts, community acceptance, and documentation and maintainability. The results show that all candidate TLOs can effectively develop BTOs, each with its distinct advantages. BFO provides a well‐structured, understandable hierarchy, and excellent query efficiency, making it suitable for integration across various ontologies and applications. PROVO demonstrates balanced performance with strong integration capabilities. Meanwhile, EMMO offers high semantic richness and domain coverage, though its complex structure impacts query efficiency and integration with other ontologies.
KW - Materials Science
KW - Ontology
KW - Knowledge Graph
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612227
DO - https://doi.org/10.1002/adem.202401534
SN - 1527-2648
SP - 1
EP - 18
PB - Wiley
AN - OPUS4-61222
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sonntag, Nadja
A1 - Piesker, Benjamin
A1 - Ávila Calderón, Luis
A1 - Mohr, Gunther
A1 - Rehmer, Birgit
A1 - Agudo Jácome, Leonardo
A1 - Hilgenberg, Kai
A1 - Evans, Alexander
A1 - Skrotzki, Birgit
T1 - Tensile and Low‐Cycle Fatigue Behavior of Laser Powder Bed Fused Inconel 718 at Room and High Temperature
N2 - This study investigates the room‐ and high‐temperature (650 °C) tensile and low‐cycle‐fatigue behavior of Inconel 718 produced by laser powder bed fusion (PBF‐LB/M) with a four‐step heat treatment and compares the results to the conventional wrought material. The microstructure after heat treatment is characterized on different length scales. Compared to the wrought variant, the elastic and yield properties are comparable at both test temperatures while tensile strength, ductility, and strain hardening capacity are lower. The fatigue life of the PBF‐LB/M variant at room temperature is slightly lower than that of the wrought material, while at 650 °C, it is vice versa. The cyclic stress response for both material variants is characterized by cyclic softening, which is more pronounced at the higher test temperature. High strain amplitudes (≥0.7%) at room temperature and especially a high testing temperature result in the formation of multiple secondary cracks at the transitions of regions comprising predominantly elongated grain morphology and columns of stacked grains with ripple patterns in the PBF‐LB/M material. This observation and pronounced crack branching and deflection indicate that the cracks are controlled by sharp micromechanical gradients and local crystallite clusters.
KW - Additive manufacturing
KW - Fatigue damage
KW - Heat treatment
KW - Inconel 718
KW - Laser powder bed fusion
KW - Low-cycle fatigue
KW - Tensile strength
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599316
DO - https://doi.org/10.1002/adem.202302122
SN - 1527-2648
SP - 1
EP - 17
PB - Wiley
AN - OPUS4-59931
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhadeliya, Ashok
A1 - Rehmer, Birgit
A1 - Fedelich, Bernard
A1 - Jokisch, T.
A1 - Skrotzki, Birgit
A1 - Olbricht, Jürgen
T1 - Fatigue crack growth behavior of Alloy 247DS brazed joints at high temperatures
N2 - Gas turbine components made of nickel-based alloys can be repaired through diffusion brazing. However, process-induced imperfections, defects within the brazing zone, and material property mismatches between the braze alloy and base material may facilitate crack initiation and propagation, ultimately leading to early component failure. To gain insight into the crack growth mechanism and quantitatively characterize fatigue crack growth behavior within brazing zones, fatigue crack growth (FCG) experiments were conducted on brazed joint specimens of nickel-based alloy Alloy 247DS at a temperature of 950 ◦C and a stress ratio R = 0.1. The FCG tests were complemented by fractographic and microstructural analyses, to elucidate the relationship between crack growth mechanisms and the microstructure of the brazed joint. The results demonstrate stable crack propagation within the brazing zone and the nickel-based braze alloy. The latter contains brittle eutectic boride phases and intermetallic phases that reduce the resistance to crack propagation compared to the parent material. This study demonstrates the applicability of standard FCG experimental procedures to fusion zones, thereby enabling a preliminary understanding of crack growth behavior in brazing zones.
KW - Diffusion brazing
KW - High-temperature fatigue crack growth
KW - Nickel-based alloys
KW - Alloy 247DS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615250
DO - https://doi.org/10.1016/j.msea.2024.147488
SN - 0921-5093
VL - 918
SP - 1
EP - 15
PB - Elsevier B.V.
AN - OPUS4-61525
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beygi Nasrabadi, Hossein
A1 - Hanke, Thomas
A1 - Skrotzki, Birgit
T1 - Semantic Representation of Low‐Cycle‐Fatigue Testing Data Using a Fatigue Test Ontology and ckan.kupferdigital Data Management System
N2 - Addressing a strategy for publishing open and digital research data, this article presents the approach for streamlining and automating the process of storage and conversion of research data to those of semantically queryable data on the web. As the use case for demonstrating and evaluating the digitalization process, the primary datasets from low‐cycle‐fatigue testing of several copper alloys are prepared. The fatigue test ontology (FTO) and ckan.kupferdigital data management system are developed as two main prerequisites of the data digitalization process. FTO has been modeled according to the content of the fatigue testing standard and by reusing the basic formal ontology, industrial ontology foundry core ontology, and material science and engineering ontology. The ckan.kupferdigital data management system is also constructed in such a way that enables the users to prepare the protocols for mapping the datasets into the knowledge graph and automatically convert all the primary datasets to those machine‐readable data which are represented by the web ontology language. The retrievability of the converted digital data is also evaluated by querying the example competency questions, confirming that ckan.kupferdigital enables publishing open data that can be highly reused in the semantic web.
KW - Accessible
KW - CKAN
KW - Interoperable
KW - Digitalizations
KW - Ontologies
KW - Reusable data
KW - Fatigue testing
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604991
UR - https://onlinelibrary.wiley.com/doi/10.1002/adem.202400675
DO - https://doi.org/10.1002/adem.202400675
SN - 1527-2648
SP - 1
EP - 11
PB - Wiley
AN - OPUS4-60499
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mrkwitschka, Paul
A1 - Rühle, Bastian
A1 - Kuchenbecker, Petra
A1 - Löhmann, Oliver
A1 - Lindemann, Franziska
A1 - Hodoroaba, Vasile-Dan
T1 - Embedding and cross-sectioning as a sample preparation procedure for accurate and representative size and shape measurement of nanopowders
N2 - Reliable measurement of the size of polydisperse, complex-shaped commercial nanopowders is a difficult but necessary task, e.g., for regulatory requirements and toxicity risk assessment. Suitable methods exist for the accurate characterization of the size of non-aggregated, stabilized, spherical and monodisperse nanoparticles. In contrast, industrial nanoscale powders usually require dedicated sample preparation procedures developed for the analysis method of choice. These nano-powders tend to agglomerate and/or aggregate, a behavior which in combination with an innate broad particle size distribution and irregular shape often significantly alters the achievable accuracy of the measured size parameters. The present study systematically tests two commercially available nanoscale powders using different sample preparation methods for correlative analysis by scanning electron microscopy, dynamic light scattering, Brunauer–Emmet–Teller method and differential mobility analysis. One focus was set on the sample preparation by embedding nanoparticles in carbon-based hot-mounting resin. Literature on this topic is scarce and the accuracy of the data extracted from cross sections of these particles is unclearly stated. In this paper systematic simulations on the deviation of the size parameters of well-defined series of nanoparticles with different shapes from the nominal value were carried out and the contributing factors are discussed.
KW - Nanopowder
KW - Electron microscopy
KW - Sample preparation
KW - Cross-sectioning
KW - Cerium oxide
KW - Zinc oxide
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593289
DO - https://doi.org/10.1038/s41598-023-51094-0
SN - 2045-2322
VL - 14
SP - 1
EP - 10
PB - Springer Nature
CY - London
AN - OPUS4-59328
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pereira, Raíssa Monteiro
A1 - Lohbauer, Ulrich
A1 - Schulbert, Christian
A1 - Göken, Mathias
A1 - Wurmshuber, Michael
A1 - Campos, Tiago Bastos Moreira
A1 - Thim, Gilmar Patrocínio
A1 - Mieller, Björn
A1 - Belli, Renan
T1 - Instantiations of Multiscale Kinship in Pressing‐Defect Distributions in Yttria‐Stabilized Zirconias by Powder Partitioning
N2 - Modern dry pressing of ceramic powders using spray‐dried granulates cannot avoid the occurrence of defects related to persisting inter‐ and intra‐granulate interstitial voids. These constitute the parent defect size population limiting the application of polycrystalline ceramics in high‐stress conditions. The mitigation of such defects could widen the range of application in technical and biomedical engineering, reduce the safety range for design, and extend the lifetime of components. Herein, the Weibull size‐effect on strength in size‐partitioned Yttria‐stabilized zirconias (YSZ) feedstocks is used to explore the viability of changing the density distribution of granulate sizes as an effective strategy to obtain a denser particle packing that could reduce the size distribution of strength‐limiting pressing defects. In a direct assessment of critical defect size using multiscale strength testing with a dataset of ≈1300 values, the success of such an approach in increasing the strength reliability for small volume components is demonstrated, along with its ultimate failure in altering the defect size distribution in sintered YSZ ceramics across several length scales. Finally, it is shown that granule morphology (spherical or dimpled) fails to affect the defect density and size distribution in YSZ ceramics.
KW - Zirconia
KW - Strength
KW - Toughness
KW - Weibull distribution
KW - Defect population
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-602697
DO - https://doi.org/10.1002/adem.202400139
SN - 1438-1656
SP - 1
EP - 17
PB - Wiley VHC-Verlag
AN - OPUS4-60269
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paulus, Daniel
A1 - Bresch, Sophie
A1 - Moos, Ralf
A1 - Schönauer-Kamin, Daniela
T1 - Powder aerosol deposited calcium cobaltite as textured P-type thermoelectric material with power factors approaching single crystal values
N2 - In this work, the thermoelectric material calcium cobaltite Ca3Co4O9 (CCO), a promising p-type conducting thermoelectric oxide with anisotropic properties, was processed by the powder aerosol deposition method (PAD) to form a dense ceramic CCO film with a thickness in the µm range. The prepared films were characterized regarding their microstructure and thermoelectric properties between room temperature and 900 °C. After heat treatment at 900 °C, the CCO PAD film in-plane shows excellent properties in terms of electrical conductivity (280 S/cm at 900 °C) and Seebeck coefficient (220 µV/K at 900 °C). The calculated power factor in-plane (ab) reaches with 1125 µW/(m K2) 40 % of the single crystal value, surpassing the known-properties of CCO bulk ceramics. Examination of the microstructure shows a strong fiber texture of the film as well as a strong coarsening of the grains during the first heat treatment up to 900 °C.
KW - thermoelectrics
KW - calcium cobaltite
KW - thermoelectric oxide
KW - aerosol deposition method (ADM)
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-606246
DO - https://doi.org/10.1016/j.jeurceramsoc.2024.116717
SN - 0955-2219
VL - 44
IS - 15
SP - 1
EP - 8
PB - Elsevier BV
AN - OPUS4-60624
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schröder, Jakob
A1 - Fritsch, Tobias
A1 - Luzin, Vladimir
A1 - Ferrari, Bruno
A1 - Simón-Muzás, Juan
A1 - Evans, Alexander
A1 - Bruno, Giovanni
T1 - Impact of scan strategy on principal stresses in laser powder bed fusion
N2 - Additive manufacturing techniques, such as laser powder bed fusion (PBF-LB), are well known for their exceptional freedom in part design. However, these techniques are also characterized by the development of large thermal gradients during production and thus residual stress (RS) formation in produced parts. In this context, neutron diffraction enables the non-destructive characterization of the bulk RS distribution. By control of the thermal gradients in the powder-bed plane by scan strategy variation we study the impact of in-process scan strategy variations on the microstructure and the three-dimensional distribution of RS. Microstructural analysis by means of electron backscatter diffraction reveals sharp microstructure transitions at the interfaces ranging from 100-200 µm. The components of the RS tensor are determined by means of neutron diffraction and the principal stress directions and magnitudes are determined by eigenvalue decomposition. We find that the distribution of RS in the powder-bed plane corresponds to the underlying scan strategy. When the alternating scan vectors align with the x- and y sample coordinate axes, the principal stress directions co-align. In the present geometry, nearly transverse isotropic stress states develop when the scan vectors are either aligned 45° between x and y or continuously rotated by 67° between each layer.
KW - Additive Manufacturing
KW - Laser Powder Bed Fusion
KW - Electron Backscatter Diffraction
KW - Neutron Diffraction
KW - Residual Stress
KW - Principal Stress
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607910
DO - https://doi.org/10.1016/j.matdes.2024.113171
SN - 0264-1275
VL - 244
SP - 1
EP - 10
PB - Elsevier Ltd.
AN - OPUS4-60791
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mieller, Björn
A1 - Hassine, Sahar Ben
A1 - Töpfer, Jörg
A1 - Priese, Christoph
A1 - Bochmann, Arne
A1 - Capraro, Beate
A1 - Stark, Sebastian
A1 - Partsch, Uwe
A1 - Fresemann, Carina
T1 - Ontology‐based Data Acquisition, Refinement, and Utilization in the Development of a Multilayer Ferrite Inductor
N2 - A key aspect in the development of multilayer inductors is the magnetic permeability of the ferrite layers. Here, the effects of different processing steps on the permeability of a NiCuZn ferrite is investigated. Dry pressed, tape cast, and co‐fired multilayer samples are analyzed. An automated data pipeline is applied to structure the acquired experimental data according to a domain ontology based on PMDco (Platform MaterialDigital core ontology). Example queries to the ontology show how the determined process‐property correlations are accessible to non‐experts and thus how suitable data for component design can be identified. It is demonstrated how the inductance of co‐fired multilayer inductors is reliably predicted by simulations if the appropriate input data corresponding to the manufacturing process is used.This article is protected by copyright. All rights reserved.
KW - Ontology
KW - Ceramic multilayer
KW - Data pipeline
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605483
DO - https://doi.org/10.1002/adem.202401042
SN - 1527-2648
SP - 1
EP - 11
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-60548
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mieller, Björn
A1 - Valavi, Masood
A1 - Caldeira Rêgo, Celso Ricardo
T1 - An Automatized Simulation Workflow for Powder Pressing Simulations Using SimStack
N2 - Automated computational workflows are a powerful concept that can improve the usability and reproducibility of simulation and data processing approaches. Although used very successfully in bioinformatics, workflow environments in materials science are currently commonly applied in the field of atomistic simulations. This work showcases the integration of a discrete element method (DEM) simulation of powder pressing in the convenient SimStack workflow environment. For this purpose, a Workflow active Node (WaNo) was developed to generate input scripts for the DEM solver using LIGGGHTS Open Source Discrete Element Method Particle Simulation code. Combining different WaNos in the SimStack framework makes it possible to build workflows and loop over different simulation or evaluation conditions. The functionality of the workflows is explained, and the added user value is discussed. The procedure presented here is an example and template for many other simulation methods and issues in materials science and engineering.
KW - Simulation workflow
KW - Discrete element method
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604791
DO - https://doi.org/10.1002/adem.202400872
SP - 1
EP - 7
PB - Wiley
AN - OPUS4-60479
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Eddah, Mustapha
A1 - Markötter, Henning
A1 - Mieller, Björn
A1 - Sintschuk, Michael
A1 - Beckmann, Jörg
A1 - Bruno, Giovanni
T1 - Mitigation of DMM-induced stripe patterns in synchrotron X-ray radiography through dynamic tilting
N2 - In synchrotron X-ray radiography, achieving high image resolution and an optimal signal-to-noise ratio (SNR) is crucial for the subsequent accurate image analysis. Traditional methods often struggle to balance these two parameters, especially in situ applications where rapid data acquisition is essential to capture specific dynamic processes. For quantitative image data analysis, using monochromatic X-rays is essential. A double multilayer monochromator (DMM) is successfully used for this aim at the BAMline, BESSY II (Helmholtz Zentrum Berlin, Germany). However, such DMMs are prone to producing an unstable horizontal stripe pattern. Such an unstable pattern renders proper signal normalization difficult and thereby causes a reduction of the SNR. We introduce a novel approach to enhance SNR while preserving resolution: dynamic tilting of the DMM. By adjusting the orientation of the DMM during the acquisition of radiographic projections, we optimize the X-ray imaging quality, thereby enhancing the SNR. The corresponding shift of the projection during this movement is corrected in post-processing. The latter correction allows a good resolution to be preserved. This dynamic tilting technique enables the homogenization of the beam profile and thereby effectively reduces noise while maintaining high resolution. We demonstrate that data captured using this proposed technique can be seamlessly integrated into the existing radiographic data workflow, as it does not need hardware modifications to classical X-ray imaging beamline setups. This facilitates further image analysis and processing using established methods.
KW - Double multilayer monochromators
KW - Synchrotron X-ray imaging
KW - Signal normalization
KW - BAMline
KW - Dynamic tilting
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615049
DO - https://doi.org/10.1107/S1600577524008646
SN - 1600-5775
VL - 31
SP - 1551
EP - 1560
PB - International Union of Crystallography (IUCr)
AN - OPUS4-61504
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zia, Ghezal Ahmad Jan
A1 - Hanke, Thomas
A1 - Skrotzki, Birgit
A1 - Völker, Christoph
A1 - Bayerlein, Bernd
T1 - Enhancing Reproducibility in Precipitate Analysis: A FAIR Approach with Automated Dark-Field Transmission Electron Microscope Image Processing
N2 - AbstractHigh-strength aluminum alloys used in aerospace and automotive applications obtain their strength through precipitation hardening. Achieving the desired mechanical properties requires precise control over the nanometer-sized precipitates. However, the microstructure of these alloys changes over time due to aging, leading to a deterioration in strength. Typically, the size, number, and distribution of precipitates for a quantitative assessment of microstructural changes are determined by manual analysis, which is subjective and time-consuming. In our work, we introduce a progressive and automatable approach that enables a more efficient, objective, and reproducible analysis of precipitates. The method involves several sequential steps using an image repository containing dark-field transmission electron microscopy (DF-TEM) images depicting various aging states of an aluminum alloy. During the process, precipitation contours are generated and quantitatively evaluated, and the results are comprehensibly transferred into semantic data structures. The use and deployment of Jupyter Notebooks, along with the beneficial implementation of Semantic Web technologies, significantly enhances the reproducibility and comparability of the findings. This work serves as an exemplar of FAIR image and research data management.
KW - Industrial and Manufacturing Engineering
KW - General Materials Science
KW - Automated image analysis
KW - FAIR research data management
KW - Reproducibility
KW - microstructural changes
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593905
DO - https://doi.org/10.1007/s40192-023-00331-5
SN - 2193-9772
SP - 1
EP - 15
PB - Springer Science and Business Media LLC
CY - Heidelberg
AN - OPUS4-59390
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bhadeliya, Ashok
A1 - Rehmer, Birgit
A1 - Fedelich, Bernard
A1 - Jokisch, Torsten
A1 - Skrotzki, Birgit
A1 - Olbricht, Jürgen
T1 - High Temperature Fatigue Crack Growth in Nickel-Based Alloys Refurbished by Additive Manufacturing
N2 - Hybrid additive manufacturing plays a crucial role in the restoration of gas turbine blades, where, e.g., the damaged blade tip is reconstructed by the additive manufacturing process on the existing blade made of a parent nickel-based alloy. However, inherent process-related defects in additively manufactured material, along with the interface created between the additively manufactured and the cast base material, impact the fatigue crack growth behavior in bi-material components. This study investigates the fatigue crack growth behavior in bi-material specimens of nickel-based alloys, specifically, additively manufactured STAL15 and cast alloy 247DS. The tests were conducted at 950 °C with stress ratios of 0.1 and −1. Metallographic and fractographic investigations were carried out to understand crack growth mechanisms. The results revealed significant retardation in crack growth at the interface. This study highlights the potential contributions of residual stresses and microstructural differences to the observed crack growth retardation phenomenon, along with the conclusion from an earlier study on the effect of yield strength mismatch on crack growth behavior at a perpendicular interface in bi-material specimens.
T2 - Superalloys 2024 Conference
CY - Champion, Pennsylvania, USA
DA - 08.09.2024
KW - Fatigue crack growth
KW - Bi-material structure
KW - Additive manufacturing
KW - Nickel-based alloys
PY - 2024
SN - 978-3-031-63937-1
DO - https://doi.org/10.1007/978-3-031-63937-1_92
SN - 2367-1181
SN - 2367-1696
VL - 15th
SP - 994
EP - 1001
PB - Springer
CY - Cham
AN - OPUS4-60907
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kindrachuk, Vitaliy
A1 - Darvishi Kamachali, Reza
T1 - Mean-field modeling and phase-field simulation of grain growth under directional driving forces
N2 - Directional grain growth is a common phenomenon in the synthetic and natural evolution of various polycrystals. It occurs in the presence of an external driving force, such as a temperature gradient, along which grains show a preferred, yet competitive, growth. Novel additive manufacturing processes, with intense, localized energy deposition, are prominent examples of when directional grain growth can occur, beneath the melting pool. In this work, we derive a phenomenological mean-field model and perform 3D phase-field simulations to investigate the directional grain growth and its underlying physical mechanisms. The effect of the intensity of driving force is simulated and systematically analyzed at the evolving growth front as well as various cross-sections perpendicular to the direction of the driving force. We found that although the directional growth significantly deviates from normal grain growth, it is still governed by a power law relation α tⁿ with an exponent n ~ 0.6–0.7. The exponent n exhibits a nontrivial dependence on the magnitude of the directional driving force, such that the lowest growth exponent is observed for intermediate driving forces. We elaborate that this can originate from the fact that the forces at grain boundary junctions evolve out of balance under the influence of the directional driving force. With increasing the driving forces, the growth exponent asymptotically approaches a value of n ≈ 0.63, imposed by the largest possible grain aspect ratio for given grain boundary energies. The current combined mean-field and phase-field framework pave the way for future exploration in broader contexts such as the evolution of complex additively manufactured microstructures.
KW - Additive manufacturing
KW - Phase-field simulation
KW - Grain growth
KW - Mean-field modelling
KW - Directional grain growth
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593210
DO - https://doi.org/10.1016/j.mtla.2023.101989
SN - 2589-1529
VL - 33
SP - 1
EP - 10
PB - Elsevier
AN - OPUS4-59321
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Karafiludis, Stephanos
A1 - Zöllner, Moritz
A1 - Eddah, Mustapha
A1 - Emmerling, Franziska
A1 - Mieller, Björn
A1 - George, Janine
A1 - Stawski, Tomasz M.
T1 - Synthesis and phase purity of the negative thermal expansion material ZrV2O7
N2 - Synthesis of pure, homogeneous, and reproducible materials is key for the comprehensive understanding, design, and tailoring of material properties. In this study, we focus on the synthesis of ZrV2O7, a material known for its negative thermal expansion properties. We investigate the influence of solid-state and wet chemistry synthesis methods on the purity and homogeneity of ZrV2O7 samples. Our findings indicate that different synthesis methods significantly impact the material's characteristics. The solid-state reaction provided high-purity material through extended milling time and repeated calcination cycles, while the sol-gel reaction enabled a “near-atomic” level of mixing and, therefore, homogenous phase-pure ZrV2O7. We confirmed purity via X-ray diffraction and Raman spectroscopy, highlighting differences between phase-pure and multiphase ceramics. These analytical techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, we were able to interpret the Raman spectra and visualise Raman active atom vibrations. We show that phase purity enables the unbiased characterisation of material properties such as negative thermal expansion.
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - XRD
KW - Raman
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624013
DO - https://doi.org/10.1039/d4tc04095c
SN - 2050-7534
SP - 1
EP - 13
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-62401
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Coburger, Peter
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Abbenseth, Josh
T1 - Combining geometric constraint and redox non-innocence within an ambiphilic PBiP pincer ligand
N2 - The first pincer ligand featuring a strictly T-shaped pnictogen donor moiety was synthesised. The PBiP ligand's redox activity facilitates unprecedented ambiphilic bonding of the Bi centre with transition metals through the Bi(6p) orbital.
KW - EXAFS
KW - Pincer Ligand
KW - Group 15 metals
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611113
DO - https://doi.org/10.1039/D4SC00197D
SN - 2041-6520
SP - 1
EP - 8
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-61111
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Valdestilhas, Andre
A1 - Bayerlein, Bernd
A1 - Moreno Torres, Benjami
A1 - Zia, Ghezal Ahmad Jan
A1 - Muth, Thilo
T1 - The Intersection Between Semantic Web and Materials Science
N2 - The application and benefits of Semantic Web Technologies (SWT) for managing, sharing, and (re-)using of research data are demonstrated in implementations in the field of Materials Science and Engineering (MSE). However, a compilation and classification are needed to fully recognize the scattered published works with its unique added values. Here, the primary use of SWT at the interface with MSE is identified using specifically created categories. This overview highlights promising opportunities for the application of SWT to MSE, such as enhancing the quality of experimental processes, enriching data with contextual information in knowledge graphs, or using ontologies to perform specific queries on semantically structured data. While interdisciplinary work between the two fields is still in its early stages, a great need is identified to facilitate access for nonexperts and develop and provide user-friendly tools and workflows. The full potential of SWT can best be achieved in the long term by the broad acceptance and active participation of the MSE community. In perspective, these technological solutions will advance the field of MSE by making data FAIR. Data-driven approaches will benefit from these data structures and their connections to catalyze knowledge generation in MSE.
KW - Linked open data
KW - Materials science
KW - Ontology
KW - Semantic web
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575506
DO - https://doi.org/10.1002/aisy.202300051
PB - Wiley-VCH GmbH
CY - Weinheim
AN - OPUS4-57550
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paskin, A.
A1 - Couasnon, T.
A1 - Perez, J. P. H.
A1 - Lobanov, S. S.
A1 - Blukis, R.
A1 - Reinsch, Stefan
A1 - Benning, L. G.
T1 - Nucleation and Crystallization of Ferrous Phosphate Hydrate via an Amorphous Intermediate
N2 - The fundamental processes of nucleation and crystallization are widely observed in systems relevant to material synthesis and biomineralization; yet most often, their mechanism remains unclear. In this study, we unravel the discrete stages of nucleation and crystallization of Fe3(PO4)2·8H2O (vivianite). We experimentally monitored the formation and transformation from ions to solid products by employing correlated, time-resolved in situ and ex situ approaches. We show that vivianite crystallization occurs in distinct stages via a transient amorphous precursor phase. The metastable amorphous ferrous phosphate (AFEP) intermediate could be isolated and stabilized. We resolved the differences in bonding environments, structure, and symmetric changes of the Fe site during the transformation of AFEP to crystalline vivianite through synchrotron X-ray absorption spectroscopy at the Fe K-edge. This intermediate AFEP phase has a lower water content and less distorted local symmetry, compared to the crystalline end product vivianite. Our combined results indicate that a nonclassical, hydration-induced nucleation and transformation driven by the incorporation and rearrangement of water molecules and ions (Fe2+ and PO4 3−) within the AFEP is the dominating mechanism of vivianite formation at moderately high to low vivianite supersaturations (saturation index ≤ 10.19). We offer fundamental insights into the aqueous, amorphous-to-crystalline transformations in the Fe2+−PO4 system and highlight the different attributes of the AFEP, compared to its crystalline counterpart.
KW - Nucleation
KW - Crystallization
KW - Vivianite
KW - Ferrous phosphate hydrate
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580696
DO - https://doi.org/10.1021/jacs.3c01494
SN - 0002-7863
VL - 145
IS - 28
SP - 15137
EP - 15151
PB - ACS Publications
AN - OPUS4-58069
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -