TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Structure-property correlations in RE-doped fluoride-phosphate glasses for scintillation
N2 - As the development of optimized glass compositions by traditional trial-and-error methods is laborious, time consuming, and expensive, it is desirable to develop glass compositions based on a fundamental understanding of the glass structure and to establish structure-property relation models. Particularly, when it comes to optical applications of glasses doped with emissive trivalent rare earth ions (RE), the chemical environmental around the ions will have a direct influence on the radiative/non-radiative emission probabilities. The local vibrational environment and the chemical nature of the bonds in the first coordination sphere of the ions can be tailored, to good extent, based on structural information given by magnetic resonance techniques (NMR and EPR), associated to Raman and photophysical characterization. For the past 5 years, while still employed at the University of São Paulo, in Brazil, one of the interests of my research group has been the development of high-density fluoride-phosphate glasses as promising UV and X-ray scintillator materials. The targeted glasses offer a lower vibrational energy, less hygroscopic fluoride environment for the RE ions whereas the phosphate network provides better mechanical and chemical stability than a purely fluoride glass matrix. Different sets of glasses, based on the compositional system (Ba/Sr)F2-M(PO3)3-MF3-(Sc/Y)F3 where M = Al, In, Ga, and the phosphate component is substituted by the fluoride analogue in 10 - 30 mol%, were investigated, using Sc3+, Y3+, and the Eu3+ and Yb3+ dopants, as structural probes. Overall, results show that the desired RE coordination by fluorine, at a given F/P ratio, is proportional to the atomic mass of M (In> Ga> Al) and that the Ga- and In- based systems differ from the Al- one by near absence of P-O-P network linkages. That is, the network structures are dominated by Ga-O-P or In-O-P linkages, as evidenced by 31P MAS-NMR and Raman. These results are nicely corroborated by observation of decreased intensity of the vibronic band in Eu3+-doped glasses and marked increase in excited state lifetime values. Radioluminescence studies were carried out for a series of In-based glasses doped with Ce3+ and Tb3+, yielding intense emissions in the blue and green, respectively, compatible to the spectral region of the highest sensitivity of radiation sensor detectors. The aim of the presentation is to show how powerful the NMR and EPR techniques can be to provide decisive structural information, and to present the research perspectives in my new role as the Head of Division 5.6 – Glass at BAM.
T2 - Fachausschusses I „Physik und Chemie des Glases“, DGG
CY - Jena, Germany
DA - 02.11.2023
KW - Structure-property correlation
KW - Fluoride phosphate glasses
KW - Scintillators
KW - High energy radiation
PY - 2024
AN - OPUS4-60360
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Glass Digitalization: Contributions from BAM
N2 - An overview of the Glass Digitalization efforts at BAM, within the framework of the Glass Digital consortium, was given. From the development of the robotic melting device to the ML capabilities, a description of the different stages of the developments and roles of project partner was presented.
T2 - GlaCerHub Melting Day
CY - Oponice, Slovakia
DA - 12.06.2024
KW - Glass Digital
KW - Robotic glass melting
KW - Digitalization
PY - 2024
AN - OPUS4-60365
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Gender equality in Sciences: Let´s teach our girls to be brave!
N2 - A panorama of the global gender gap scenario in sciences, specially STEM, was given to illustrate the need for urgent actions (and suggestions of them) to correct biased treatment and promote females in their scientific careers.
T2 - FunGlass School
CY - Oponice, Slovakia
DA - 10.06.2024
KW - Gender gap
KW - Women in science
KW - Female noble prize winners
PY - 2024
AN - OPUS4-60366
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Spectroscopy Lectures
N2 - As a guest professor of FUNGLASS, I delivered 3 lectures on spectroscopy to the Graduate School Program, the postdoctoral fellows and other researchers: 1) Introduction to spectroscopy applied to solid state materials (with focus on glass and glass ceramics); 2) Vibrational spectroscopy (Infrared and Raman); 3) Electron Paramagnetic Resonance
T2 - FunGlass
CY - Trencín, Slovakia
DA - 03.06.2024
KW - Spectroscopy
KW - Radiation-matter interaction
KW - FT-IR
KW - Raman
KW - EPR
PY - 2024
AN - OPUS4-60367
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - From guest scintillators to luminescent host-guest hybrid materials and nanoparticles: Contributions from LEMAF
N2 - An overview of the research work conducted at LEMAF - the laboratory of spectroscopy of functional materials in IFSC/USP Brazil under my leadership, before I joined BAM was given.
T2 - FunGlass Graduate Program School
CY - Oponice, Slovakia
DA - 10.10.2023
KW - Multifunctional nanoparticles
KW - Structure property correlations
KW - Host-guest hybrid materials
KW - Scintillators
KW - Persistent luminescent
KW - Phosphors
KW - Composite materials
PY - 2024
AN - OPUS4-60368
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Gender equality in sciences: Let's teach our girls to be brave!
N2 - A global panorama of the Gender Gap in Sciences was presented along with recommendations on how to remediate unequal treatment of females in Science, and to prepare future generations for gender equality.
T2 - Lunch Talk - Women@DGM: Gender Mindsets/Bias in an International Context
CY - Online meeting
DA - 14.06.2024
KW - Gender gap
PY - 2024
AN - OPUS4-60369
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Camargo, Andrea Simone Stucchi
T1 - Optical properties of glasses and ceramics
N2 - Optical glasses and glass ceramics are present in many devices often used in our daily routine, such as the mobile phones and tablets. Since the 1960´s with the development of glass lasers, and more recently, within the search for efficient W-LEDs, sensors and solar converters, this class of materials has experienced extreme research progress. In order to tailor a material for such applications, it is very important to understand and characterize optical properties such as refractive index, transmission window, absorption and emission cross sections, quantum yields, etc. These properties can often be tuned by appropriate compositional choice and post-synthesis processing. In this lecture we will discuss the optical properties of glasses and glass ceramics, relevant to that end.
T2 - 2nd CeRTEV Glass School
CY - São Carlos, SP, Brazil
DA - 22.04.2024
KW - Optical properties of glasses and ceramics
PY - 2024
AN - OPUS4-60370
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bayerlein, Bernd
T1 - PMD core ontology: Building Bridges at the Mid-Level – A Community Effort for 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 and variant knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific.
This poster presents an approach to create and maintain a comprehensive and intuitive MSE-centric terminology by developing a mid-level ontology–the PMD core ontology (PMDco)–via MSE community-based curation procedures.
The PMDco is designed in direct support of the FAIR principles to address immediate needs of the global experts community and their requirements. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics, how the PMDco lowers development and integration thresholds, and how to fuel it from real-world data sources ranging from manually conducted experiments and simulations as well as continuously automated industrial applications.
T2 - TMS - Specialty Congress 2024
CY - Cleveland, Ohio, US
DA - 16.06.2024
KW - Interoperability
KW - Semantic Interoperability
KW - Digtial Representation
KW - Knowledge graph and ontologies
PY - 2024
AN - OPUS4-60378
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bayerlein, Bernd
T1 - Digital Transformation in Materials Science: Insights From the Platform MaterialDigital (PMD)
N2 - The digital era has led to a significant increase in innovation in scientific research across diverse fields and sectors. Evolution of data-driven methodologies lead to a number of paradigm shifts how data, information, and knowledge is produced, understood, and analyzed. High profile paradigm shifts in the field of materials science (MS) include exploitative usage of computational tools, machine learning algorithms, and high-performance computing, which unlock novel avenues for investigating materials. In these presentations, we highlight prototype solutions developed in the context of the Platform MaterialDigital (PMD) project that addresses digitalization challenges. As part of the Material Digital Initiative, the PMD supports the establishment of a virtual materials data space and a systematic handling of hierarchical processes and materials data using a developed ontological framework as high priority work items. In particular, the mid-level ontology PMDco and its augmentation through application-specific ontologies are illustrated. As part of the conclusion, a discussion encompasses the evolutionary path of the ontological framework, taking into account standardization efforts and the integration of modern AI methodologies such as natural language processing (NLP). Moreover, demonstrators illustrated in these presentations highlight: The integration and interconnection of tools, such as digital workflows and ontologies, Semantic integration of diverse data as proof of concept for semantic interoperability, Improved reproducibility in image processing and analysis, and Seamless data acquisition pipelines supported by an ontological framework. In this context, concepts regarding the application of modern research data management tools, such as electronic laboratory notebooks (ELN) and laboratory information management systems (LIMS), are presented and elaborated on. Furthermore, the growing relevance of a standardized adoption of such technologies in the future landscape of digital initiatives is addressed. This is supposed to provide an additional basis for discussion with respect to possible collaborations.
T2 - NIST Seminar on Digital Transformation
CY - Gaithersburg, MD, USA
DA - 11.06.2024
KW - Digital Transformation
KW - Research Data Management
KW - Ontology
KW - Reusability
KW - FAIR
PY - 2024
AN - OPUS4-60381
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Trappe, Volker
T1 - Glasfaser-Halbzeuge im Anwendungsbereich der CS 22 - Drapieren, Altern, Schwingfestigkeit
N2 - Glasfaserkunststoff – GFK – wurde im Segelflugzeugbau mit der FS 24 „Phönix“ seit 1957 in tragenden Strukturen verbaut. Auch wenn in moderneren Luftfahrzeugen Carbon-Faser-Kunststoff – CFK – das GFK in weiten Teilen der Flugzeugstruktur zur Gewichtseinsparung und wegen der höheren Steifigkeit verdrängt hat, so findet sich GFK heute noch im Holm-Steg und anderen hoch belasteten Strukturbauteilen.
Nach dem Motto „höher, schneller, weiter“, wurden die Glasfaser-Textilien mit Haftvermittlern (Schlichte / Finish) versehen, um eine gute Anbindung zwischen der Glasfaser und der Epoxid-Harz-Matrix zu bekommen. Hierzu wurden zunächst Chrom-Verbindungen eingesetzt, die seit der Einführung der REACH-Verordnung 2007 bezüglich der Umweltbelastung problematisch sind. Infolgedessen haben die Hersteller der Glasfaser-Textilien alternative Schlichte- / Finish- Systeme entwickelt, die den „Alten“ in den Gebrauchseigenschaften vergleichbar sein sollten. Hinsichtlich der nach RHV geforderten Schwingfestigkeit war es 2004 erforderlich, den Vorgabewert von 1985 moderat abzusenken, damit die neuen Halbzeuge für den Einsatz im Segelflugzeugbau zugelassen werden konnten. Zudem verschlechterte sich teilweise die Drapier-Fähigkeit der neuen Glasfasergewebe, auch wenn die Schwingfestigkeit ausreichend gut war.
Im Rahmen einer Masterarbeit wurde Anfang 2024 an der BAM im Fachbereich 5.3 – Polymere Verbundwerkstoffe – vergleichend fünf im Markt verwendete Glasfaser-Textilien hinsichtlich der Drapier-Fähigkeit untersucht. Zudem wurden die Halbzeuge bei einer erhöhten Luftfeuchtigkeit und Temperatur ausgelagert und dann zu GFK-Proben verarbeitet. Schließlich wurden „as received“ Proben und gealterte +/-45°-Proben nach RHV schwingend beansprucht. Im Rahmen dieses Vortrags wurde das Projekt sowie die Ergebnisse erstmal der Leichtflugzeugindustrie vorgestellt.
T2 - 48. Symposium für Flugzeugentwicklung 2024
CY - Braunschweig, Germany
DA - 14.11.2024
KW - Faserkunststoffverbunde
KW - Flugzeugbau
KW - Alterung
PY - 2024
AN - OPUS4-62182
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Loose, Florian
T1 - CFK-Recycling
N2 - Obwohl der Leichtbau mit carbonfaserverstärkten Kunststoffen (CFK) einen wichtigen Beitrag zum Klimaschutz und zur Ressourceneffizienz liefert, stellt der wachsende Abfallstrom von aktuell 62 kt/a eine große Herausforderung dar. Weil die Produktion von Carbonfasern (CF) überwiegend auf fossilen Rohstoffen basiert und sehr energieintensiv ist, werden nachhaltige Recyclinglösungen dringend benötigt. Hier wird ein Überblick über aktuelle Recyclingprozesse gegeben und deren Limitierungen diskutiert. Darüber hinaus wird eine Möglichkeit zur sicheren chemischen Nutzung von CF-haltigen Reststoffen aufgezeigt, die nicht zur Wiederverwertung geeignet sind. Das Projekt CF Pyro untersucht deren Einsatz als Sekundärrohstoff in der Pyrometallurgie und setzt besondere Schwerpunkte bei der Reaktivität von CF, der Prozessstabilität und der Vermeidung von Emissionen gesundheitsschädlicher WHO-Fasern. Abschließend wird eine, auf den experimentellen Ergebnissen und im Dialog mit Expertinnen und Experten aus Wirtschaft, Wissenschaft und Politik entwickelten, Technologiebewertung vorgestellt.
T2 - 4. Netzwerktreffen Leichtbau Berlin-Brandenburg
CY - Berlin, Germany
DA - 01.10.2024
KW - Cabonfasern
KW - Recycling
PY - 2024
AN - OPUS4-61279
LA - deu
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 - Montazerian, Maziar
A1 - Mauro, John C.
A1 - de Camargo, Andrea S. S.
T1 - Richard Adolf Zsigmondy: Nobel laureate and pioneer in optical glasses
N2 - Austrian chemist Richard A. Zsigmondy was known for his work in colloid chemistry, but his research inspired advancements in optical glasses as well.
KW - Quantum dots
KW - Glass
KW - Richard Zsigmondy
PY - 2024
VL - 103
IS - 9
SP - 38
EP - 40
AN - OPUS4-62590
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Blaeß, Carsten
T1 - Binder jetting of crystallizing bioactive glass powders
N2 - Customized artificial bone replacement implants made of resorbable bioactive glass (BG) have not yet become widely accepted in clinical use. This is mainly due to the contrariness of sintering ability and appropriate bioactivity. Concurrent crystallization often prevents the generation of dense sinter bodies, especially for additive manufactured 3D scaffolds. The presented study investigates the limits and advantages of crystallization of powder compacts manufactured by binder jetting and uniaxial pressing for different particle size fractions (psf) of two BGs.
T2 - CeramicAM 2024 - 1º
CY - Sao Paulo, Brasil
DA - 19.09.2024
KW - Bioactive glass
KW - Sintering
KW - Crystallization
KW - Additive manufacturing
PY - 2024
AN - OPUS4-62594
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 - GEN
A1 - Rosenbusch, Sjard Mathis
A1 - Diercks, Philipp
A1 - Kindrachuk, Vitaliy
A1 - Unger, Jörg F.
T1 - Integrating custom constitutive models into FEniCSx: A versatile approach and case studies
N2 - The development and integration of user-defined constitutive relationships into finite element (FE) tools using standardized interfaces play a pivotal role in advancing the capabilities of FE solvers for structural mechanics applications. While commercial FE solvers like Abaqus and Ansys have designed their interfaces to provide custom stresses, tangents, and updated history variables, the open-source solver FEniCSx remains efficient only when the constitutive update has an analytical representation. This restricts the application of FEniCSx for non-linear structural mechanics.
Since FEniCSx has become a powerful and popular open-source tool for solving partial differential equations, particularly due to its automatic computation of Hessians, we aim to develop a generalized interface to enhance its capability for constitutive modeling. This approach will address complex constitutive equations that require iterative solutions at the quadrature point level. Specific implementation challenges, such as using return-mapping procedures, can then be managed commonly. The provided interface for custom constitutive models offers a versatile way to implement them in various languages, including C++, Python, Rust, and Fortran. Finally, using the example of UMATs for viscoplastic models, we demonstrate how available user subroutines can be incorporated into the interface while maintaining computational performance of FEniCSx comparable to that of Abaqus.
KW - Finite element method
KW - Constitutive models
KW - FEniCSx
KW - UMAT
KW - Rust
KW - Python
KW - C++
PY - 2024
DO - https://doi.org/10.5281/zenodo.13980988
PB - Zenodo
CY - Geneva
AN - OPUS4-62112
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Lindemann, Franziska
T1 - Bestimmung der spezifischen Oberfläche mittels Gasadsorption (BET-Verfahren)
N2 - Im Rahmen des 2. BAM-Akademie Info-Tages "Nano or not Nano" wurde die OECD TG 124 "Volume Specific Surface Area of Manufactured Nanomaterials" vorgestellt.
Der Vortrag beschreibt die Bestimmung der spezifischen Oberfläche von dispersen und/oder porösen Pulvern mittels Gasadsorption nach dem BET-Verfahren.
Es wird auf die Anwendbarkeit der Methode eingegangen und es werden praktische Hinweise zur Probenvorbereitung und Messung von Nanomaterialien gegeben.
T2 - BAM Akademie II: Info-Tage "Nano or not Nano"
CY - Online meeting
DA - 25.01.2024
KW - OECD TG 124
KW - Nanopulver
KW - VSSA
KW - Nano powder
KW - BET
KW - Spezifische Oberfläche
PY - 2024
AN - OPUS4-59623
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kuchenbecker, Petra
T1 - Bestimmung der Skelettdichte mittels Gaspyknometrie
N2 - Im Rahmen des 2. BAM-Akademie Info-Tages "Nano or not Nano" wurde die OECD TG 124 "Volume Specific Surface Area of Manufactured Nanomaterials" vorgestellt. Der Vortrag beschreibt detailliert das Messverfahren der He-Gaspyknometrie zur Bestimmung der Skelettdichte von Pulvern und geht auf Anwendbarkeit, Besonderheiten bei Nanopulvern und wichtige Einstellparameter für die Messung ein.
T2 - BAM Akademie II: Info-Tage "Nano or not Nano"
CY - Online meeting
DA - 25.01.2024
KW - Pycnometry
KW - Density
KW - Nano powder
PY - 2024
AN - OPUS4-59561
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kuchenbecker, Petra
T1 - Einführung: Volume Specific Surface Area (VSSA)
N2 - Im Rahmen der 2. BAM-Akademie-Veranstaltung "Nano or not Nano" wurde die OECD TG 124 "Volume Specific Surface Area of Manufactured Nanomaterials" vorgestellt.
Der Vortrag enthält ein Einführung zur VSSA mit Definitionen, Vorteilen und Einschränkungen.
T2 - BAM Akademie II: Info-Tage "Nano or not Nano"
CY - Online meeting
DA - 25.01.2024
KW - Nano powder
KW - VSSA
KW - Specific surface
KW - OECD TG
PY - 2024
AN - OPUS4-59560
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kuchenbecker, Petra
T1 - Herausforderungen bei der Granulometrie von (technischen) Nano-Pulvern
N2 - Einführungsvortrag im Rahmen der Veranstaltung der BAM-Akademie zur Anwendung der OECD TG 124 "Volume Specific Surface Area of Manufactured Nanomaterials" zu Herausforderungen bei der Granulometrie von Nanopulvern. Es werden die Einflüsse von Partikelform, Breite der Partikelgrößenverteilung und Agglomeration/ Aggregation auf das Messergebnis sowie die Vergleichbarkeit der Ergebnisse verschiedener Messverfahren dargelegt.
T2 - BAM Akademie II: Info-Tage "Nano or not Nano"
CY - Online meeting
DA - 25.01.2024
KW - Nanopulver
KW - Granulometrie
KW - Partikelgröße
KW - VSSA
KW - OECD TG 124
PY - 2024
AN - OPUS4-59558
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Swaminathan, Srinivasan
A1 - Kumar, S.
A1 - Kranzmann, Axel
A1 - Hesse, Rene
A1 - Goldbeck, Hennig
A1 - Fantin, Andrea
T1 - Corrosion characteristics of 316L stainless steel in oxide-rich molten solar salt at 600◦C
N2 - An attempt has been made in this work, to observe the influence on alloy aging by the sodium oxide (Na2O) in solar salt (60 wt% NaNO3 + 40 wt% KNO3). The accelerated aging was established by adding Na2O (0.005, 0.07, 0.135 and 0.2 wt%) to the solar salt and their effect on corrosion of 316L stainless steel (SS) at 600 ◦C in that oxide-rich solar salts for 168 h in synthetic air was investigated. Corrosion is significantly more in oxide-rich solar salt compared to pure solar salt. Strikingly, the oxide scale-base metal interface is wavy in solar salt containing 0.005 % Na2O clearly shows the oxide addition to salt melt influences Cr-rich inner oxide layer formation and its selective dissolution at early stage that leads to non-uniform corrosion. Interestingly, with increase of Na2O to 0.07 %, steel corrosion proceeded uniformly by accelerated disintegration of Cr-rich inner layer and subsequent dissolution. Severe scale spallation and weight loss in nitrate melt containing 0.2 % Na2O fostering more rapid corrosion, alarming that substantial tolerance of oxide content in solar salt is ≥ 0.135 % for an acceptable corrosion of 316L SS. Despite preferential dissolution of Cr and scale degradation/spallation with increased oxide content in solar salt, the corrosion layer in all cases comprised of sodium ferrite, and Cr-rich Cr-Fe mixed oxides with the Ni enrichment at the scale-metal interface. Competing processes between oxide scale growth, degradation and dissolution or even spallation has been discussed with an emphasis of Na2O addition to solar salt.
KW - Molten salt corrosion
KW - Solar salt
KW - Thermal energy storage
KW - Stainless steel
KW - Concentrating solar power
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610819
DO - https://doi.org/10.1016/j.solmat.2024.113176
VL - 278
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-61081
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Kalady, Mohammed Fayis
A1 - Schultz, Johannes
A1 - Weinel, Kristina
A1 - Wolf, Daniel
A1 - Lubk, Axel
T1 - Localization of Hybridized Surface Plasmon Modes on Random Gold Nanoparticle Assemblies
N2 - Assemblies of plasmonic nanoparticles (NPs) support hybridized modes of localized surface plasmons (LSPs), which delocalize in geometrically well-ordered arrangements. Here, the hybridization behavior of LSPs in geometrically completely disordered arrangements of Au NPs fabricated by an e-beam synthesis method is studied. Employing electron energy loss spectroscopy in a scanning transmission electron microscope in combination with numerical simulations, the disorder-driven spatial and spectral localization of the coupled LSP modes that depend on the NP thickness is revealed. Below 0.4nm sample thickness (flat NPs), localization increases towards higher hybridized LSP mode energies. In comparison, above 10nm thickness, a decrease of localization (an increase of delocalization) with higher mode energies is observed. In the intermediate thickness regime, a transition of the energy dependence of the localization between the two limiting cases, exhibiting a transition mode energy with minimal localization, is observed. This behavior is mainly driven by the energy and thickness dependence of the polarizability of the individual NPs.
KW - Plasmonics
KW - Electron-Energy Loss Spectroscopy
KW - Discrete Dipole Approximation
KW - Nanoparticles
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618323
DO - https://doi.org/10.48550/arXiv.2410.10514
SP - 1
EP - 8
PB - Cornell University
CY - Ithaca, NY
AN - OPUS4-61832
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Werner, Tiago
A1 - Teske, Tanita
A1 - Hilgenberg, Kai
A1 - Mauro, Madia
A1 - Nielsen, S.
A1 - Gärtner, F.
A1 - Klassen, T.
T1 - Untersuchung des Potenzials von Kaltgasspritzen für die Reparatur zyklisch belasteter Bauteile
T1 - Investigation on the capability of cold-spray for repair of cyclically loaded components
N2 - Die Reparatur mittels Kaltgasspritzen ist eine vielversprechende Alternative zum
teuren Austausch fehlerbehafteter Bauteile in der Luft- und Raumfahrt. Im Rahmen
dieser Arbeit wurde das Potential des Verfahrens an der hochfesten
Aluminiumlegierungen Al6061-T6 unter Anwendung von Stickstoff als kostengünstiges
Prozessgas untersucht. Es wurden quasi-statische Zugversuche und einachsige
Zeitfestigkeitsversuche mit besonderem Fokus auf das in-situ Kugelstrahlen zur
Verbesserung der mechanischen Eigenschaften durchgeführt. Im Ergebnis wurde die
Verbesserung der Adhäsion zwischen Substrat und aufgebautem Werkstoff als
entscheidendes Kriterium für eine Anwendbarkeit ermittelt. Die Laserstrukturierung
von Substratoberflächen ist hierfür vielversprechend und wurde im Rahmen der Arbeit
mittels Adhäsionsversuchen untersucht.
N2 - Repair by cold-spray is a promising alternative to the costly replacement of flawed
components in aerospace applications. In the present work this process was
investigated on the high-strength aluminum alloy Al6061-T6. For the cold-spray
process, inexpensive Nitrogen was used as process-gas. Quasi-static tensile and highcycle-
fatigue tests (HCF) were performed, focusing on in-situ shot peening to improve
the mechanical properties of the repaired part. An improved adhesion between
substrate and built-up material was identified as a key-factor for the applicability of the
process. Under this respect laser-structuring of the substrate surface was applied and
its effect on the mechanical performance of the restored samples were examined by
adhesion tests.
T2 - 9. Tagung des DVM-Arbeitskreises Additiv gefertigte Bauteile und Strukturen
CY - Stuttgart, Germany
DA - 06.11.2024
KW - Kaltgasspritzen
KW - cold-spray
KW - Reparatur
KW - Repair
KW - Ermüdungsfestigkeit
KW - Fatigue
KW - Luft- und Raumfahrt
KW - Aerospace
KW - Substratvorbehandlung
KW - Substrate pre-treatment
PY - 2024
DO - https://doi.org/10.48447/ADD-2024-BB
VL - 409
SP - 67
EP - 79
AN - OPUS4-63182
LA - deu
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 - CONF
A1 - Weinel, Kristina
T1 - Plasmonic Behavior in Assemblies of Disordered Gold Nanoparticles
N2 - Plasmons are collective oscillations of the free electron density in metals which can be described by an electromagnetic field. Surface plasmons are longitudinal waves propagating at the surface of the metallic material coupled to an external field. Localized surface plasmons on a nanoparticle reveal the behavior of standing waves with discrete resonance frequencies whose dominating mode is called dipole mode. Coupling of nanoparticles leads eventually to a hybridization of those dipole modes and therefore to spectral and spatial delocalization which was already investigated in ordered systems. In disordered systems, there are a lot of open questions regarding the propagation behavior which changes from delocalization to localization for instance due to the disorder. This phenomenon is then called Anderson localization. To investigate the propagation behavior of plasmonic waves in an assembly of disordered gold NPs, we combine experimental results of electron energy loss spectroscopy in a scanning transmission microscope with simulation results of the self-consistent dipole modelling. We indeed find experimentally localization of plasmon modes and with the simulation we could exclude other localization mechanism such as life-time damping or retardation. In conclusion, we could found Anderson localization of surface plasmons in assemblies of disordered gold nanoparticles which will enhance the understanding of this kind of vector waves to the Anderson localization as a general wave behavior in disordered systems.
T2 - PhD seminar Leipniz Institut for solid state and material research (IFW Dresden)
CY - Dresden, Germany
DA - 19.06.2024
KW - Plasmonic
KW - EELS in STEM
KW - Self-consistent dipole model
KW - Assemblies of gold nanoparticles
PY - 2024
AN - OPUS4-60945
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 - CONF
A1 - Wojciak, K.
A1 - Tokarski, T.
A1 - Cios, G.
A1 - Nolze, Gert
T1 - Precision and accuracy during standard-less mapping of local lattice distortions using ebsd and calm technique
N2 - Electron Back Scatter Diffraction (EBSD) is a very versatile analytical technique allowing for the characterization of material structure. Historically, diffraction images (Kikuchi patterns) registered during EBSD analysis were solved using Hough/Radon transformation. The last decade brought several novel techniques of experimental pattern analysis, focusing entirely on image analysis routines such as pattern matching, or various variants of High-Resolution EBSD. However, all the above-mentioned techniques require prior knowledge of the material structure to perform orientation analysis. The recently presented algorithm employed in Crystallographic Analysis of Lattice Metric (CALM) software, effectively removes this limitation enabling a standard-less analytical approach in EBSD systems. At its core, the CALM technique couples accurate detection of the Kikuchi bands position, with a rigid construction of reciprocal lattice resulting from translational crystal symmetry. A unique characteristic of the methodology also gives an opportunity for application in the analysis of continuous lattice changes, for example tetragonality mapping. During mapping, however, the geometry of the gnomonic projection (represented by the projection center) is continuously altered decreasing overall algorithm efficiency. The work presents an analysis of the projection center in terms of precision and accuracy.
T2 - Oxford User Meeting 2024
CY - Krakow, Poland
DA - 14.05.2024
KW - EBSD
KW - Kikuchi
KW - Lattice parameters
KW - Ratio refinement
PY - 2024
AN - OPUS4-60087
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Tokarski, T.
A1 - Nolze, Gert
T1 - Exploring Unconventional Uses of Kikuchi Pattern Analysis
N2 - The characterization of really unknown phases typically uses 70 to 150 reflectors for lattice metric calculation. The determination of the lattice parameters follows with 4% accuracy. Including a Z correction up to 1% can be reached. The precision of the lattice parameters ratios (a:b:c) is, however, better than 0.1%.
T2 - Oxford Users Meeting 2024
CY - Krakow, Poland
DA - 14.05.2024
KW - EBSD
KW - Kikuchi
KW - Lattice parameters
KW - Ratio refinement
PY - 2024
AN - OPUS4-60086
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 - CONF
A1 - Bettge, Dirk
T1 - Merkmale von alltäglichen Brüchen und wie wir daraus lernen können
N2 - Schadensfälle aus dem Alltag erscheinen oft simpel, sind im Detail aber meist komplexer als erwartet und eröffnen die Möglichkeit, Merkmale zu studieren, Aufnahmetechniken und Bildbearbeitung zu optimieren und die Erfahrungen am Ende ohne Restriktionen weiter zu vermitteln. Beispielsweise verändern sich die mikroskopischen Merkmale von Schwingrissen über ihren Verlauf oft deutlich. Dies hängt von der Art des Werkstoffs und von den Beanspruchungsbedingungen ab. Die Bruchmerkmale werden schließlich systematisch dargestellt und ein Datensatz für die Fraktographische online-Datenbank der DVM/DGM AG Fraktographie erstellt, die fachöffentlich einsehbar ist.
T2 - Metallographietagung 2024
CY - Berlin, Germany
DA - 18.09.2024
KW - Fraktographie
KW - Schadensanalyse
PY - 2024
AN - OPUS4-61239
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kalinka, Gerhard
T1 - Moderne Faserverbundwerkstoffe – Reparatur und Recycling
N2 - Der Vortrag beschreibt Aktivitäten der BAM zur Reparatur von Rotorblättern von Windkraftanlagen sowie ein Konzept zum Recycling by Design für faserverstärkte Kunststoffe
T2 - Reparaturgerechtes Produktdesign
CY - Potsdam, Germany
DA - 06.11.2024
KW - GFRP
KW - Rotorblätter
KW - Reparatur
KW - Recycling
KW - Composites
PY - 2024
AN - OPUS4-61533
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kalinka, Gerhard
T1 - Recycling von Faserverbundwerkstoffen
N2 - Der Vortrag beschreibt Aktivitäten der BAM zum Recycling von carbonfaser-verstärkten Verbundwerkstoffen.
T2 - Fachdialog Recycling von Windenergieanlagen
CY - Berlin, Germany
DA - 23.09.2024
KW - Polymer Matrix Composite
KW - Carbon Fibres
KW - Recycling
KW - Pyrolysis
KW - Recycling by Design
PY - 2024
AN - OPUS4-61536
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Junge, Paul
A1 - Rupprecht, Christian
A1 - Sänger, Johanna
A1 - Oedinghofen, Frank
T1 - Thermisch gespritzte Schichten auf keramischen Hitzeschutzschilden für den Einsatz regenerativer Brennstoffe in stationäre Gasturbinen
T1 - Thermally sprayed coatings on ceramic heat shields
for the utilisation of regenerative fuels in stationary gas turbines
N2 - Die Entwicklung zukünftiger Generationenvon stationären Gasturbinen verfolgt das Hauptziel, den thermischen Wirkungsgrad zu erhöhen, bei gleichzeitiger Reduktion der CO2-Emissionen. Ein mögliches Lösungskonzept besteht darin, bestehende Turbinenkonzepte auf nachhaltig erzeugten Wasserstoff umzustellen. Durch den Betrieb mit Wasserstoff entsteht eine erhöhte Belastung für konventionelle thermische Hitzeschutzkomponenten. Daher ist die Entwicklung von sogenannte Environmental Barrier Coatings (EBC) oder Materialkonzepten, die eine thermodynamische Stabilität in heißer Gasumgebung aufweisen, erforderlich.
N2 - The development of future generations of stationary gas turbines is
pursuing the main objective of increasing the thermal efficiency, with a simultaneous reduction in the CO2 emissions. One possible solution concept consists of converting existing turbine concepts to sustainably produced hydrogen. The operation with hydrogen results in increased loads for conventional thermal heat protection components. Therefore, it is necessary to develop so-called environmental barrier coatings (EBCs) or material concepts which exhibit thermodynamic stability in a hot gas environment
KW - Keramischen Hitzeschutzschilden
KW - Thermische Spritzschichten
KW - Gasturbine
PY - 2024
UR - https://www.thermal-spray-bulletin.info/en/article/thermisch-gespritzte-schichten-auf-keramischen-hitzeschutzschilden-fuer-den-einsatz-regenerativer-brennstoffe-in-stationaeren-gasturbinen
IS - 2
SP - 100
EP - 103
PB - DVS Media
AN - OPUS4-61066
LA - mul
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bayerlein, Bernd
T1 - Semantic integration of diverse data in materials science: Assessing Orowan strengthening
N2 - This 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 darkfield 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 [1], facilitates this integration. This approach adheres to FAIR principles and enables sophisticated analysis via SPARQL queries, revealing correlations consistent with the Orowan mechanism (see Fig.1). The study highlights the potential of semantic data integration in MSE, offering a new approach for data-centric research and enhanced analytical capabilities [2].
T2 - MSE Congress 2024 - Materials Science and Engineering
CY - Darmstadt, Germany
DA - 24.09.2024
KW - Semantic Representation
KW - Age-Hardenable Aluminium Alloy
KW - Digtial Representation
KW - Knowledge graph and ontologies
KW - PMD Core Ontology
PY - 2024
AN - OPUS4-61139
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Trappe, Volker
T1 - Advanced lightweight applications – recycling versus reliability and fossil energy footprint
N2 - Advanced light weight applications like aircrafts and wind turbine blades are made of fibre reinforced plastics (FRP) with continuous fibre reinforcement and must withstand a high thermo-mechanical cyclic loading. The quality of the fibre matrix interface has a high impact on the fatigue life and was continuously improved over the years since the 50th. The fatigue life of glass fibre reinforced plastics (GFRP) used in aircraft industry is 10 to 100 times higher compared to glass fibre non crimp fabrics used for wind turbine blades.
To assure a constant and reliable high quality and strength of reinforcement fibres, synthetic fibre production is state of the art (CF, GF). There is a need for recycling GFRP and CFRP waste due to the upcoming use. Pyrolysis and solvolysis are more expensive than the mechanical route however enable a more sustainable recycling. Natural fibres and recycled synthetic fibres have a high scatter in quality and strength. Hence it is a challenge to optimize the production / recycling processes to get a reliable quality for any demanding (second life) application.
Chemical routes for using renewables resources and recycling, is going to be a good approach especially for polymer-matrix systems to get 100% quality (back) compared to the state of the art.
Finally, a proper design, life-time extension and repair is preferable to recycling to keep the carbon footprint as low as possible.
T2 - 27. INTERNATIONALES DRESDNER LEICHTBAUSYMPOSIUM
CY - Dresden, Germany
DA - 13.06.2024
KW - Polymer Matrix Composites
KW - Carbon Fibre
KW - Recycling
KW - Circular Economy
PY - 2024
UR - https://leichtbausymposium.de/deu/
AN - OPUS4-60683
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 - CONF
A1 - Reinsch, Stefan
T1 - Oriented Surface Crystallization in Glasses
N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. For silicate glasses we found a good correlation between the calculated surface energy of crystal faces and oriented surface nucleation. Surface energies were estimated assuming that crystal surfaces resemble minimum energy crack paths along the given crystal plane. This concept was successfully applied at the Institute of Physics of Rennes in calculating fracture surface energies of glasses. Several oriented nucleation phenomena can be herby explained assuming that high energy crystal surfaces tend to be wetted by the melt. This would minimize the total interfacial energy of the nucleus. Furthermore, we will discuss the evolution of the microstructure and its effect on the preferred crystal orientation.
T2 - ACerS GOMD 2024- Glass & Optical Materials Division Meeting
CY - Las Vegas, NV, USA
DA - 19.05.2024
KW - Surface nucleation
KW - Oriented surface crystallization
KW - Surface energy
PY - 2024
AN - OPUS4-60238
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Reinsch, Stefan
T1 - Oriented Surface Crystallization in Glasses
N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. For silicate glasses we found a good correlation between the calculated surface energy of crystal faces and oriented surface nucleation. Surface energies were estimated assuming that crystal surfaces resemble minimum energy crack paths along the given crystal plane. This concept was successfully applied at the Institute of Physics of Rennes in calculating fracture surface energies of glasses. Several oriented nucleation phenomena can be herby explained assuming that high energy crystal surfaces tend to be wetted by the melt. This would minimize the total interfacial energy of the nucleus. Furthermore, we will discuss the evolution of the microstructure and its effect on the preferred crystal orientation.
T2 - 13th International Symposium on Crystallization in Glasses and Liquids
CY - Orléans, France
DA - 24.09.2024
KW - Surface crystallization
KW - Surface energy
KW - Crystal orientation
KW - Silicate glass
PY - 2024
AN - OPUS4-62219
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waurischk, Tina
T1 - GlasDigital - Datengetriebener Workflow für die beschleunigte Glasentwicklung
N2 - Im Projekt GlasDigital sollen digitale Werkzeuge für die Hochdurchsatzentwicklung neuartiger Glaswerkstoffe erarbeitet werden. Dies soll durch die Kombination robotischer Syntheseverfahren mit selbstlernenden Maschinen und ihre Einbindung in eine Ontologie-basierte digitale Infrastruktur realisiert werden.
T2 - 4. Fachsymposium der Fachgruppe Glasapparatebauer
CY - Mitterteich, Germany
DA - 13.06.2024
KW - Glas
KW - Ontology
KW - Data Space
KW - Simulation
KW - Workflow
KW - Robotische Schmelzanlage
PY - 2024
AN - OPUS4-60388
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waurischk, Tina
T1 - Digital infrastructure for accelerated glass development
N2 - Glasses stand out by their wide and continuously tunable chemical composition and large variety of unique shaping techniques making them a key component of modern high technologies. Glass development, however, is still often too cost-, time- and energy-intensive. The use of robotic melting systems embedded in an ontology-based digital environment is intended to overcome these problems in future.
For this purpose, a robotic high throughput glass melting system is equipped with novel inline sensors for process monitoring, machine learning (ML)-based, adaptive algorithms for process monitoring and optimization, novel tools for high throughput glass analysis and ML-based algorithms for glass design. This includes software tools for data mining as well as property and process modelling. The presentation provides an overview of how all these tools merge into a digital infrastructure and illustrates their usability using examples.
All infrastructural parts were developed by a consortium consisting of the Fraunhofer ISC in Würzburg, the Friedrich-Schiller-University Jena (OSIM), the Clausthal University of Technology (INW) and the Federal Institute for Materials Research and Testing (BAM, Division Glasses) as part of a joint project of the German research initiative MaterialDigital.
T2 - 97. Glass-Technology Conference
CY - Aachen, Germany
DA - 27.05.2024
KW - Glass
KW - Robotic melting
KW - Ontologie
KW - Simulation
KW - Workflow
KW - Data Space
KW - Digital Twin
PY - 2024
AN - OPUS4-60387
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Blaeß, Carsten
T1 - Undesired Foaming of Silicate Glass Powders
N2 - The manufacture of sintered glasses and glass-ceramics, glass matrix composites, and glass-bounded ceramics or pastes is often affected by un-expected gas bubble formation also named foaming. Against this background, in this presentation the main aspects and possible reasons of foaming are shown for completely different glass powders: a barium silicate glass powders used as SOFC sealants, and bioactive glass powders using different powder milling procedures.
Sintering and foaming were measured by means of heating microscopy backed up by XRD, differential thermal analysis (DTA), vacuum hot extraction (VHE), optical and electron microscopy, and infrared spectroscopy, and time-of-flight secondary ion mass spectrometry (ToF-SIMS).
Different densification was reached followed by significant foaming starting partly immediately, partly at higher temperature. Foaming increased significantly as milling progressed. For moderately milled glass powders, subsequent storage in air could also promote foaming. Although the milling atmosphere significantly affects the foaming of uniaxially pressed powder compacts sintered in air.
VHE studies show that foaming is driven by carbon gases and carbonates were detected by Infrared spectroscopy to provide the major foaming source. Carbonates could be detected even after heating to 750 °C, which hints on a thermally very stable species or mechanical trapping or encapsulating of CO2. Otherwise, dark gray compact colors for milling in isopropanol indicate the presence of residual carbon as well. Its significant contribution to foaming, however, could not be proved and might be limited by the diffusivity of oxygen needed for carbon oxidation to carbon gas.
T2 - Seminário de Laboratório de Materiais Vítreos (LaMaV) de Departamento de Engenharia de Materiais (DEMa), Universidade Federal São Carlos UFSCar)
CY - Saint Charles, Brazil
DA - 06.06.2024
KW - Bioactive
KW - Foaming
KW - Glass
KW - Crystallization
KW - Viscose sintering
PY - 2024
AN - OPUS4-60245
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Stargardt, Patrick
T1 - H2 permeability of soda-lime, borosilicate and vitreous silica glasses for potential high pressure H2 storage applications
N2 - Modern high-pressure H2 tanks consist of fiber-reinforced composite materials and a plastic lining on the inside. The use of glass would drastically increase the H2 barrier effect. This could be achieved with glass liners or fiber-reinforced polymer-bonded glass capillary storage tanks and would enable lower wall thicknesses, higher gravimetric storage densities and variable designs and thus a much more effective use of space.
However, the decisive material parameters for the development of these technologies, such as the hydrogen permeation, are unknown. This study focuses on H2 diffusion in glasses of different chemical compositions.
H2 permeation is measured by mass spectrometry. For this purpose, the mass spectrometer (MS), which is located in a high vacuum, is separated from the pressure side by the test specimen. Pure H2 gas is present on the pressure side, so that the mass flow is recorded qualitatively and quantitatively in the MS. The permeation coefficients are calculated from the sample geometry and the mass flow rates. The very low H2 permeation of glass is measured on bundles of thin-walled commercially available glass capillaries and compared with the hydrogen permeation data of the glass powder method.
T2 - Jahrestagung der Deutschen Glastechnischen Gesellschaft 2024
CY - Aachen, Germany
DA - 27.05.2024
KW - Gas permeation
KW - Hydrogen gas
KW - High pressure gas storage
PY - 2024
AN - OPUS4-60420
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Reinsch, Stefan
T1 - Orientierte Oberflächenkristallisation in Gläsern
N2 - Bislang wird das Phänomen der orientierten Oberflächenkristallisation kontrovers diskutiert und entsprechende Studien beschränken sich auf nur wenige Gläser. Für Silikatgläser haben wir eine gute Korrelation zwischen der berechneten Oberflächenenergie von Kristallflächen und der orientierten Oberflächenkeimbildung gefunden. Die Oberflächenenergien wurden unter der Annahme abgeschätzt, dass die Kristalloberflächen bei der Keimbildung den Kristallebenen mit minimaler Energie entsprechen, denen ein Riss beim Bruch folgt. Dieses Konzept wurde am Institut für Physik in Rennes erfolgreich bei der Berechnung der Bruchflächenenergien von Gläsern angewandt. Mehrere orientierte Keimbildungsphänomene lassen sich dadurch erklären, dass man annimmt, dass Kristalloberflächen mit hoher Energie dazu neigen, von der Schmelze benetzt zu werden. Dies minimiert die gesamte Grenzflächenenergie des Keims. Darüber hinaus werden wir die Entwicklung der Mikrostruktur beim weiteren Kristallwachstum und ihre Auswirkungen auf die bevorzugte Kristallorientierung diskutieren.
T2 - 21. Treffen des DGG-DKG Arbeitskreises „Glasig-kristalline Multifunktionswerkstoffe“
CY - Mainz, Germany
DA - 22.02.2024
KW - Oberflächenkeimbildung
KW - Kristallorientierung
KW - Grenzflächenenergie
PY - 2024
AN - OPUS4-60237
LA - mul
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 - Mohring, Wencke
A1 - Karafiludis, Stephanos
A1 - Manzoni, Anna Maria
A1 - Laplanche, G.
A1 - Schneider, M.
A1 - Stephan-Scherb, Christiane
T1 - High-Temperature Corrosion of High- and Medium-Entropy Alloys CrMnFeCoNi and CrCoNi Exposed to a Multi-Oxidant Atmosphere H2O–O2–SO2
N2 - AbstractThe high-temperature corrosion behaviors of the equimolar CrCoNi medium-entropy alloy and CrMnFeCoNi high-entropy alloy were studied in a gas atmosphere consisting of a volumetric mixture of 10% H2O, 2% O2, 0.5% SO2, and 87.5% Ar at 800 °C for up to 96 h. Both alloys were initially single-phase fcc with a mean grain size of ~ 50 μm and a homogeneous chemical composition. The oxide layer thickness of CrMnFeCoNi increased linearly with exposure time while it remained constant at ~ 1 μm for CrCoNi. A Cr2O3 layer and minor amounts of (Co,Ni)Cr2O4 developed on the latter while three oxide layers were detected on the former, i.e., a thin and continuous chromium rich oxide layer at the oxide/alloy interface, a dense (Mn,Cr)3O4 layer in the center and a thick and porous layer of Mn3O4 and MnSO4 at the gas/oxide interface. Additionally, a few metal sulfides were observed in the CrMnFeCoNi matrix. These results were found to be in reasonable agreement with thermodynamic calculations.
KW - high entropy alloys
KW - corrosion
KW - oxidation
KW - scanning electron microscopy
KW - sulfidation
KW - CrMnFeCoNi
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594189
DO - https://doi.org/10.1007/s44210-023-00026-8
SP - 1
EP - 17
PB - Springer Science and Business Media LLC
AN - OPUS4-59418
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 - INPR
A1 - Weinel, Kristina
A1 - Hahn, Marc Benjamin
A1 - Lubk, Axel
A1 - Feng, Wen
A1 - Martinez, Ignacio Gonzalez
A1 - Büchner, Bernd
A1 - Agudo Jácome, Leonardo
T1 - Electron-beam-induced modification of gold microparticles in an SEM
N2 - Electron-beam-induced conversion of materials in a transmission electron microscope uses the high power density of a localized electron beam of acceleration voltages above 100 kV as an energy source to transform matter at the sub-micron scale. Here, the e-beam-induced transformation of precursor microparticles employing a low-energy e-beam with an acceleration voltage of 30 kV in a scanning electron microscope is developed to increase the versatility and efficiency of the technique. Under these conditions, the technique can be classified between e-beam lithography, where the e-beam is used to mill holes in or grow some different material onto a substrate, and e-beam welding, where matter can be welded together when overcoming the melting phase. Modifying gold microparticles on an amorphous SiOx substrate reveals the dominant role of inelastic electron-matter interaction and subsequent localized heating for the observed melting and vaporization of the precursor microparticles under the electron beam. Monte-Carlo scattering simulations and thermodynamic modeling further support the findings.
KW - Scanning electron microscopy
KW - Electron-beam-induced modification
KW - Heat transfer
KW - Gold microparticles
KW - Nanoparticles synthesis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609513
UR - https://arxiv.org/html/2408.02409v1
SP - 1
EP - 9
AN - OPUS4-60951
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 - CONF
A1 - Prabhakara, Prathik
T1 - Ein synergistischer Ansatz zur Charakterisierung anisotroper Materialien mit Hilfe von Ultraschall und Mikrostrukturanalyse
N2 - Es wird eine Studie zur Charakterisierung eines anisotropen Stahls vorgestellt, bei der Ultraschalluntersuchungen mit Mikrostrukturanalysen verbunden werden. Das Material weist hohe Festigkeit und Korrosionsbeständigkeit auf, zugleich ist mit anisotropen Eigenschaften die mechanischen und betrieblichen Eigenschaften beeinflussen zu rechnen. Vorläufige Ergebnisse lassen vermuten, dass weitere Untersuchungen notwendig sind, um die Fähigkeiten und Grenzen des Materials genau zu bestimmen. Es wird ein systematischer Ansatz mit Array- Prüfköpfen, Time-of-Flight Diffraction (TOFD) Technik und mikrostrukturellen Untersuchungen angewendet, um die Wechselwirkung zwischen Anisotropie und Mikrostruktur des Stahls zu analysieren. Ultraschallprüfungen mit der TOFD-Technik und in Tauchtechnik liefern Einblicke in das anisotrope Verhalten des Werkstoffes, einschließlich entsprechenden Kornorientierung, Dämpfung und Schallgeschwindigkeitsvariation. Diese Messungen führen in Verbindung mit mikrostrukturellen Analysen zu einem tieferen Verständnis des Materialverhaltens. Unser Hauptziel ist es, ein Framework zu erstellen, welches die Ultraschallantwort anisotroper Materialien mit ihren mikroskopischen Struktureigenschaften verbindet. Die vorgestellte Methodik ermöglicht eine zerstörungsfreie und zügige Bewertung der Materialintegrität, was besonders bei der Anwendung von Hochleistungsmaterialien relevant ist. Durch diesen integrativen Ansatz werden verschiedener Charakterisierungsmethoden kombiniert, um ein umfassenderes Materialverständnis zu erreichen.
T2 - DGZfP-Jahrestagung 2024
CY - Osnabrück, Germany
DA - 06.05.2024
KW - Ultrasonic Testing
KW - Time-offlight Diffraction (TOFD)
KW - Microstructure Analysis
KW - Non-Destructive Testing
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600122
UR - https://www.ndt.net/?id=29535
AN - OPUS4-60012
LA - deu
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 - Gogula, Shravya
A1 - Bornhöft, H.
A1 - Wondraczek, L.
A1 - Sierka, M.
A1 - Diegeler, A.
A1 - Müller, Ralf
A1 - Deubener, J.
T1 - Optical Real-Time Castability Evaluation for High-Throughput Glass Melting
N2 - A novel optical real-time method for evaluating the castability of glass forming melts for laboratory furnaces is presented. The method is based on the analysis of top view images of the melt surface inside the crucible during melting after being subjected to a small mechanical impulse. In this way, the melt surface is excited to oscillate. The difference in contrast between two images taken in quick succession scales with the viscosity, with a larger difference occurring at lower viscosities. The method is designed as an instrument for the in-line evaluation of the castability for a high-throughput glass melting system as part of the joint project “GlasDigital” in the framework of the German Platform Material Digital initiative but is applicable to other laboratory furnaces as well.
KW - Optical Real-Time Castability Check
KW - Image Analysis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618659
DO - https://doi.org/10.52825/glass-europe.v2i.1359
VL - 2
SP - 83
EP - 93
AN - OPUS4-61865
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weinel, Kristina
T1 - Heat-driven synthesis of gold nanoparticles from gold microparticles in an e-beam of an SEM
N2 - The synthesis of gold nanoparticles from a microparticle precursor were done by illuminating the precursor with an e-beam in an SEM. To understand the driving physical mechanism, a model for thermodynamic calculation were set up and solved numerically. The results support not charging, but heat as the main mechanism.
T2 - IFW annual PhD seminar
CY - Görlitz, Germany
DA - 22.10.2024
KW - Heat-driven synthesis
KW - Scanning Electron Microscopy
KW - Nanoparticle synthesis
PY - 2024
AN - OPUS4-61834
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weinel, Kristina
A1 - Schultz, Johannes
A1 - Kalady, Mohammed Fayis
A1 - Wolf, Daniel
A1 - Agudo Jácome, Leonardo
A1 - Lubk, Axel
T1 - Fabrication of 2-dimensional disordered assemblies of gold nanoparticles and investigation of localized surface plasmon resonances
N2 - Interaction of electromagnetic waves, such as electron beams or light, with conductive material can lead to localized surface plasmon resonances (LSPRs) where the incoming energy can be deposited in a collective excitation of electrons of the conduction band, which in turn can result in coherent localized plasmon oscillations. LSPR in metallic nanostructures, such as nanoparticles (NPs), which are sensitive to geometry, material composition and environment, are currently utilized in a wide range of applications, such as surface-enhanced Raman spectroscopy, plasmonic wave guides, improved solar cells, on-chip particle accelerators and nanoantennas. A host of studies that focus on plasmonic NPs ranging from single NPs with several shapes (cubic, spherical, tetrahedral) over 1D assemblies of NPs such as chains, to ordered 2D assemblies of NPs show an increase of the complexity regarding the hybridization behavior of LSPRs eventually lead to delocalized Surface Plasmons. Furthermore, Anderson predicted in 1977 the absence of diffusion or delocalization of waves in disordered systems, which has been discussed as the underlying mechanism for LSPRs localization in disordered metallic thin films and ultrathin 2D networks. Our aim is to further develop these studies on the surface plasmon localization in disordered structures by (1) developing a novel NPs assembly fabrication method that allows fabricating disordered assemblies of NPs of a wide range of NPs sizes, and (2) probing the LSPR with high-resolution electron energy-loss spectroscopy (EELS). Moreover, the dominant dipolar interaction between the NPs, also facilitates an efficient numerical modeling of these systems, which in comparison with the experiments allows for an in-depth study of the impact of various geometric parameters as well as retardation and life-time damping on the observed localization behavior.
To synthesize 2D disordered assemblies of gold NPs on a TEM transparent silicon oxide substrate, a new synthesis routine was developed. This procedure is based on sublimation and redeposition of a gold microparticle precursor induced by an electron beam in a scanning electron microscope (SEM) operated at 30 kV. To characterize the assembly of synthesized NPs in terms of size, shape and spreading over the substrate, TEM measurements were conducted subsequently. To study LSPRs experimentally, EELS in scanning transmission electron microscopy (STEM) mode was carried out. The numerical modelling of LSPRs was performed using a self-consistent dipole model.
The synthesized 2D disordered gold NPs assemblies exhibit a gradient in the NPs mean size, which ranges from 100 nm close to the precursor location down to 2 nm at a distance of more than 20 µm from the precursor location. Additionally, the interparticle distance between the gold NPs increases with increasing distance to the precursor location.
The experimental investigation as well as the numerical simulation of the LSPRs demonstrate a localization behavior that decreases toward larger energies, which is driven by the disorder of the NPs assembly (mainly the random particle distance). That localization behavior stays in contrast to what was found in ultrathin 2D gold networks showing increasing of localization towards higher LSPRs energies. By varying the geometric parameters of the NPs assembly in the simulation, we could identify the NPs thickness as the parameter, that determines the energy-dependence of the localization. Specifically, a critical thickness of approx. 10 nm separates the two localization regimes, which correlates to the energy of the dipole mode resonance crucially depending on the thickness of the NPs.
2D disordered assemblies of gold NPs of a wide range of NPs sizes and distances can be synthesized directly on thin substrates facilitating structural characterization and EELS measurements in a TEM. It could be shown that such assemblies exhibit LSPRs with a localization behavior that may be tuned by the NPs sizes (including thickness) and interparticle distances. The proposed synthesis of random NPs assemblies opens new avenues for fundamental studies on Anderson localization in disordered plasmonic structures as well as its applications such as surface-enhanced Raman spectroscopy where localization behavior must be tuned to specific wave lengths.
T2 - 17th European Microscopy Congress (EMC 2024)
CY - Copenhagen, Denmark
DA - 26.08.2024
KW - Scanning electron microscopy
KW - Gold nanoparticle synthesis
KW - Disordered assemblies
KW - Localized surface plasmon resonances
KW - Transmission electron microscopy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618330
DO - https://doi.org/10.1051/bioconf/202412932007
VL - 129
SP - 1
EP - 2
PB - EDP Sciences
CY - Les Ulis
AN - OPUS4-61833
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Manzoni, Anna Maria
T1 - High temperature oxidation of the CrFeNi medium entropy alloy
N2 - The oxidation behaviour of any alloy is a key issue which determines whether this material is suited for application. In this study, a single-phase equiatomic CrFeNi alloy was exposed to synthetic air at 1000 - 1100 °C for 24 - 1000 h and compared to 316L steel. The oxidation rate of CrFeNi was parabolic at the lower temperatures 1000 °C and 1050 °C, but at 1100 °C a first breakaway occurred after 4 h of exposure. In all cases, the oxide scales were found to partially spall off. As expected, Cr diffuses outwards to form a Cr2O3 layer at the gas/oxide interface. A thin layer of (Cr, Fe, Ni)3O4 is identified at the oxide/alloy interface. The CrFeNi alloy does not show any catastrophic oxidation behaviour at the investigated conditions unlike the 316L alloy, which contains more Mn and Fe.
T2 - MSE 2024
CY - Darmstadt, Germany
DA - 24.08.2024
KW - Corrosion
KW - Medium entropy alloy
KW - Scanning electron microscopy
PY - 2024
AN - OPUS4-62434
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Agudo Jácome, Leonardo
T1 - The Al4-xZr5(Ox-y) Trojan horse in the AlMo0.5NbTiTa0.5Zr refractory high entropy superalloy
N2 - Unlike conventional alloys, which typically consist of one main element, high-entropy alloys (HEAs) contain five or more principal elements, which broaden chemical complexity and with it a realm of synergistic mechanisms. The AlMo0.5NbTa0.5TiZr HEA initiated a subclass of Al-containing refractory (r)HEAs that has recently drawn attention [2]. The alloy has a superalloy-resembling B2/bcc nanostructure, which inspired its name refractory high entropy superalloy (RSA). With high-temperature (HT) compressive strengths beyond conventional Ni-based superalloys, this nanostructure could be used for improved HT structural applications. However, in the application-relevant HT regime the Al-Zr-rich B2 phase decomposes to form a hexagonal Al-Zr-based intermetallic (Al4-xZr5; x: 0..1) [3,4]. This work explores the fascinating yet fatal micromechanisms associated to this phase transformation, in the context of creep, annealing and oxidation experiments performed between 800 and 1200 °C.
The material was produced by arc-melting and heat treatment in argon, which lead to grain boundaries decorated with up to 7%. Interrupted constant-load creep tests were performed under vacuum (at 10-4 Pa), at 900–1100 °C with external tensile stresses of 30–120 MPa. Oxidation experiments were separately conducted for 24 hours at 800 and 1000 °C in both dry (21% O2 + 79% N2) and humid (8% O2 + 74% N2 + 18% H2O) air. After the experiments, the samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy to reveal degradation mechanisms. Crystallographic texture, orientation relationships and stabilization of an oxygen-containing iso structure (Al4-xZr5(Ox-y); y: 0..x) of the Al-Zr-rich intermetallic are found and discussed.
T2 - BCC Superalloy Network Opening Workshop
CY - Reutte, Austria
DA - 08.02.2024
KW - High entropy alloy
KW - Superalloy
KW - Degradation
KW - Electron microscopy
KW - Microstructure
PY - 2024
AN - OPUS4-59833
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weinel, Kristina
T1 - Fabrication of 2D assemblies of disordered gold nanoparticles and investigation of localized surface plasmon resonances
N2 - Interaction of electromagnetic waves, such as electron beams or light, with conductive material can lead to localized surface plasmon resonances (LSPRs) where the incoming energy can be deposited in a collective excitation of electrons of the conduction band, which in turn can result in coherent localized plasmon oscillations. LSPR in metallic nanostructures, such as nanoparticles (NPs), which are sensitive to geometry, material composition and environment, are currently utilized in a wide range of applications, such as surface-enhanced Raman spectroscopy, plasmonic wave guides, improved solar cells, on-chip particle accelerators and nanoantennas. A host of studies that focus on plasmonic NPs ranging from single NPs with several shapes (cubic, spherical, tetrahedral) over 1D assemblies of NPs such as chains, to ordered 2D assemblies of NPs show an increase of the complexity regarding the hybridization behavior of LSPRs eventually lead to delocalized Surface Plasmons. Furthermore, Anderson predicted in 1977 the absence of diffusion or delocalization of waves in disordered systems, which has been discussed as the underlying mechanism for LSPRs localization in disordered metallic thin films and ultrathin 2D networks. Our aim is to further develop these studies on the surface plasmon localization in disordered structures by (1) developing a novel NPs assembly fabrication method that allows fabricating disordered assemblies of NPs of a wide range of NPs sizes, and (2) probing the LSPR with high-resolution electron energy-loss spectroscopy (EELS). Moreover, the dominant dipolar interaction between the NPs, also facilitates an efficient numerical modeling of these systems, which in comparison with the experiments allows for an in-depth study of the impact of various geometric parameters as well as retardation and life-time damping on the observed localization behavior.
To synthesize 2D disordered assemblies of gold NPs on a TEM transparent silicon oxide substrate, a new synthesis routine was developed. This procedure is based on sublimation and redeposition of a gold microparticle precursor induced by an electron beam in a scanning electron microscope (SEM) operated at 30 kV. To characterize the assembly of synthesized NPs in terms of size, shape and spreading over the substrate, TEM measurements were conducted subsequently. To study LSPRs experimentally, EELS in scanning transmission electron microscopy (STEM) mode was carried out. The numerical modelling of LSPRs was performed using a self-consistent dipole model.
The synthesized 2D disordered gold NPs assemblies exhibit a gradient in the NPs mean size, which ranges from 100 nm close to the precursor location down to 2 nm at a distance of more than 20 µm from the precursor location. Additionally, the interparticle distance between the gold NPs increases with increasing distance to the precursor location.
The experimental investigation as well as the numerical simulation of the LSPRs demonstrate a localization behavior that decreases toward larger energies, which is driven by the disorder of the NPs assembly (mainly the random particle distance). That localization behavior stays in contrast to what was found in ultrathin 2D gold networks showing increasing of localization towards higher LSPRs energies. By varying the geometric parameters of the NPs assembly in the simulation, we could identify the NPs thickness as the parameter, that determines the energy-dependence of the localization. Specifically, a critical thickness of approx. 10 nm separates the two localization regimes, which correlates to the energy of the dipole mode resonance crucially depending on the thickness of the NPs.
2D disordered assemblies of gold NPs of a wide range of NPs sizes and distances can be synthesized directly on thin substrates facilitating structural characterization and EELS measurements in a TEM. It could be shown that such assemblies exhibit LSPRs with a localization behavior that may be tuned by the NPs sizes (including thickness) and interparticle distances. The proposed synthesis of random NPs assemblies opens new avenues for fundamental studies on Anderson localization in disordered plasmonic structures as well as its applications such as surface-enhanced Raman spectroscopy where localization behavior must be tuned to specific wave lengths.
T2 - 17th European Microscopy Congress (EMC 2024)
CY - Copenhagen, Denmark
DA - 26.08.2024
KW - Transmission electron microscopy
KW - Scanning electron microscopy
KW - Localized surface plasmon resonances
KW - Gold nanoparticle synthesis
KW - Disordered assemblies
PY - 2024
AN - OPUS4-60947
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Manzoni, Anna Maria
T1 - Two decades of cuboids in high entropy alloys
N2 - One of the original concepts of high entropy alloys was the use of single-phase alloys that were strengthened by the presence of many different main elements. After some years of research, it was found that this strengthening could be enhanced further by the introduction of a carefully chosen second phase that has a connection to the matrix phase. A most suitable combination is the combination of a ductile matrix phase with a disordered structure and an intermetallic precipitation phase that is coherent to the matrix. The most well-known example is the gamma-gammaprime morphology that is known from Ni-base superalloys, but it is not the only one. Combination of fcc-B2 or bcc-B2 have been discovered and optimized in several alloys and they lead the materials to beautiful microstructures with admirable properties.
This talk presents the different types of cuboid formations in HEAs that have been presented in the last two decades.
T2 - 32nd International Materials Research Congress - IMRC 2024
CY - Cancun, Mexico
DA - 18.08.2024
KW - High entropy alloys
KW - Chemically complex materials
KW - Transmission electron microscopy
PY - 2024
AN - OPUS4-60935
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Prabhakara, Prathik
T1 - Ein synergistischer Ansatz zur Charakterisierung anisotroper Materialien mit Hilfe von Ultraschall und Mikrostrukturanalyse
N2 - Es wird eine Studie zur Charakterisierung eines anisotropen Stahls vorgestellt, bei der Ultraschalluntersuchungen mit Mikrostrukturanalysen verbunden werden. Das Material weist hohe Festigkeit und Korrosionsbeständigkeit auf, zugleich ist mit anisotropen Eigenschaften die mechanischen und betrieblichen Eigenschaften beeinflussen zu rechnen. Vorläufige Ergebnisse lassen vermuten, dass weitere Untersuchungen notwendig sind, um die Fähigkeiten und Grenzen des Materials genau zu bestimmen. Es wird ein systematischer Ansatz mit Array- Prüfköpfen, Time-of-Flight Diffraction (TOFD) Technik und mikrostrukturellen Untersuchungen angewendet, um die Wechselwirkung zwischen Anisotropie und Mikrostruktur des Stahls zu analysieren. Ultraschallprüfungen mit der TOFD-Technik und in Tauchtechnik liefern Einblicke in das anisotrope Verhalten des Werkstoffes, einschließlich entsprechenden Kornorientierung, Dämpfung und Schallgeschwindigkeitsvariation. Diese Messungen führen in Verbindung mit mikrostrukturellen Analysen zu einem tieferen Verständnis des Materialverhaltens. Unser Hauptziel ist es, ein Framework zu erstellen, welches die Ultraschallantwort anisotroper Materialien mit ihren mikroskopischen Struktureigenschaften verbindet. Die vorgestellte Methodik ermöglicht eine zerstörungsfreie und zügige Bewertung der Materialintegrität, was besonders bei der Anwendung von Hochleistungsmaterialien relevant ist. Durch diesen integrativen Ansatz werden verschiedener Charakterisierungsmethoden kombiniert, um ein umfassenderes Materialverständnis zu erreichen.
T2 - DGZfP-Jahrestagung 2024
CY - Osnabrück, Germany
DA - 06.05.2024
KW - Ultrasonic Testing
KW - Material Characterization
KW - Microstructure Analysis
KW - Time-offlight Diffraction (TOFD)
KW - Non-Destructive Testing
PY - 2024
UR - https://www.ndt.net/?id=29535
AN - OPUS4-60980
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weinel, Kristina
T1 - Electron-beam-induced synthesis and characterization of disordered plasmonic gold nanoparticle assemblies
N2 - Several studies have been shown that the electron beam can be used to create nanomaterials from microparticle targets in situ in a transmission electron microscope (TEM). Here, we show how this method has to be modified in order to synthesize plasmonic gold nanoparticles (NPs) on insulating silicon oxide substrate by employing a scanning electron microscope with a comparatively low acceleration voltage of 30 kV. The synthesized NPs exhibit a random distribution around the initial microparticle target: Their average size reduces from 150 nm to 3 nm with growing distance to the initial Au microparticle target. Similarly, their average distance increases. The synthesized NP assemblies therefore show distinctly different plasmonic behaviour with growing distance to the target, which allows to study consequences of random hybridization of surface plasmon in disordered system, such as Anderson localization. To reveal the surface plasmons and their localization behaviour we apply electron energy loss spectroscopy in the TEM.
T2 - DPG spring conference, condensed matter section
CY - Berlin, Germany
DA - 17.03.2024
KW - Scanning electron microscopy
KW - Gold nanoparticle synthesis
KW - Disordered assemblies
KW - Localized plasmons
PY - 2024
AN - OPUS4-59763
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - RPRT
A1 - Kuchenbecker, Petra
A1 - Lindemann, Franziska
T1 - Final report proficiency test LS BAM-5.4-2024 - Measurement of the particle size distribution of ceramic powders by laser diffraction
N2 - This publication is the final report on the proficiency test (PT) LS BAM-5.4-2024 „Measurement of the particle size distribution of ceramic powders by laser diffraction”. The PT was organized by the Federal Institute for Materials Research and Testing (BAM), division 5.4 “Advanced Multi-materials Processing”, Germany. The measurements took place from 2024/05 to 2024/07. The aim of the interlaboratory comparison was the proficiency assessment of the participating laboratories. The PT was performed in accordance with DIN EN ISO/IEC 17043:2010. The harmonized measurement procedure was based on ISO 13320:2020The statistical analysis was performed in accordance with DIN ISO 13528:2020 by use of the software PROLab (QuoData GmbH, Dresden, Germany). A group of 35 laboratories from 14 countries participated in the PT. Laser diffraction analyzers produced by 7 different manufacturers were used. The three test materials were commercial ceramic powders. Overall, the measured characteristic values of the particle size distributions (d10,3, d50,3 and d90,3) were in the size range between 1 and 35 μm. The final report contains all individual results in an anonymous form.
KW - Proficiency test
KW - Particle size determination
KW - Laser diffraction
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610602
DO - https://doi.org/10.26272/opus4-61060
SP - 1
EP - 33
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61060
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Fedelich, Bernard
T1 - On the cubic slip effect and creep anisotropy modeling of single crystal superalloys at intermediate temperatures (IT)
N2 - Low-Temperature High Stress (LTHS) creep plays a crucial role in Ni-base Superalloys, particularly affecting components like blades near the root. Below 850°C, the precipitate microstructure remains stable, characterized by periodically arranged ’ cubic precipitates surrounded by the -matrix. In these conditions, macroscopic traces of cubic slip have been observed in <111> oriented tensile specimens, whereas their microscopic origin has been a topic of debate. Furthermore, in LTHS conditions, Superlattice Intrinsic, Extrinsic Stacking Faults (SISF/SESF), or micro-twins are also frequently reported in crept specimens. Usually, these mechanisms are investigated separately, so that a unified picture and a detailed understanding of these mechanisms and their activation conditions have only recently emerged in the literature, despite the intensive investigations of the last decades.
The objective of this work is to develop a dislocation-based constitutive law that includes these recent developments. In particular, the pseudo-cubic slip mechanism is considered as resulting from the lack of hardening in <111> oriented tensile specimens and is represented by a novel estimate of the back-stresses based on the spectral decomposition of a tensorial representation of the back-stress. An additional novelty is that SISF- and SESF-related slip systems are accounted for as distinct slip systems with corresponding dislocation densities. The model has been implemented as a user-defined constitutive law for commercial Finite Element codes and identified as well as validated with data from the literature obtained with <001>, <011> and <111> oriented crystals tested in tension and compression creep.
T2 - International Conference on Material Modelling (8)
CY - London, GB
DA - 15.07.2024
KW - Creep
KW - Superalloy
KW - Crystal plasticity
KW - Single crystal
PY - 2024
AN - OPUS4-60744
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 - GEN
A1 - Ávila Calderón, Luis
A1 - Schriever, Sina
T1 - BAM Reference Data: Creep of Single-Crystal Ni-Based Superalloy CMSX-6
N2 - This publication provides comprehensive metadata and test results of constant force creep tests according to DIN EN ISO 204:2019-4 on the single crystal Ni-based superalloy CMSX-6 at T = 980 °C and initial stresses between 140 MPa and 230 MPa. The tests were carried out in an accredited test laboratory using calibrated measuring equipment. The data were audited and are BAM reference data.
KW - NFDI-MatWerk
KW - Digitalisierung
KW - CMSX-6
KW - Creep
KW - Reference Data
KW - Referenzdaten
KW - Ni-Based Superalloy
PY - 2024
DO - https://doi.org/10.5281/zenodo.13937986
PB - Zenodo
CY - Geneva
AN - OPUS4-61649
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Kindrachuk, Vitaliy
T1 - Computational investigation of DGG kinetics by phase-field method
N2 - Non-equilibrium microstructure evolution in additive manufacturing (AM) is a major barrier for establishing a safe and sustainable application of AM in industrial processes. The constant heat source in the AM continuously affects the just-solidified grains beneath the melting pool, leading to directional grain growth (DGG). While real-time measurements of the non-equilibrium microstructure evolution is challenging, here developing a computational framework to systematically explore DGG becomes imperative.
We have advanced a comprehensive approach, integrating mean-field modeling and phase-field simulations, to elucidate the dynamics of DGG under an external driving force. Our simulations unveil a steady-state power-law grain growth kinetics during DGG, characterized by the interplay between curvature-driven dynamics at grain boundary junctions and directional driving forces.
T2 - Tagung DGM Additive Fertigung
CY - Bremen, Germany
DA - 12.06.2024
KW - Directional grain growth
KW - Phase-field simulation
KW - Additive manufacturing
PY - 2024
AN - OPUS4-60750
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Marschall, Niklas
T1 - Phase Decomposition in Magnetic FeMnNiCoCu Alloy System
N2 - Phase decomposition in multi-component high-entropy alloys (HEAs) can take complex routes, on the one hand, leading to various safety concerns during their service and, on the other hand, opening vast opportunities for intelligent alloy design. Insights into a controlled decomposition of initially homogeneous HEAs are therefore essential. In this study, we combine the recently developed multi-component elastic energy theory with CALPHAD databases to study potentially magnetic FeMnNiCoCu alloy system. In a first approximation, the elastic energy is added to the Gibbs free energy to reconstruct the thermodynamic phase diagrams and consequent phase decompositions. Our results show that depending on the alloy composition and the temperature, Cu-rich and FeCo-rich phases emerge, which lead to the formation of distinct magnetic phases of different extents. The spatial redistribution of elements is studied through Fourier analysis, auto-, and cross-correlation, revealing the contribution of the thermodynamic, kinetic and elastic driving forces throughout this process. These dissembled analysis methods contribute to a more comprehensive understanding of multi-component alloys and the role of elastic energy in their phase decomposition.
T2 - MSE2024
CY - Darmstadt, Germany
DA - 23.09.2024
KW - High-Entropy Alloy
KW - Elasticity
KW - Spinodal Decomposition
KW - FeMnNiCoCu
PY - 2024
AN - OPUS4-62341
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Murugan, Jegatheesan
T1 - Thermodynamics of Grain Boundary Segregation in Fe-Ni-Cr Alloy Systems
N2 - Phase stability in multi-components alloy systems is still largely unknown, especially at the internal interfaces. Grain boundary (co-)segregation is one of the main causes of instability and therefore safety issues in microstructures. In this work, the segregation in FCC Fe-Ni-Cr alloy system, which is the base for several steels, super-alloys and high entropy alloys, is studied. The density-based phase-field model is advanced to compute the segregation of Fe, Ni and Cr at the grain boundary corresponding to the bulk composition. Here the relative density of the grain boundary to the bulk is the mean-field parameter of the model. The necessary thermodynamic parameters of the bulk are obtained from the CALPHAD database. We performed high-throughput screening of the elemental segregation at the grain boundary across the stable bulk compositions at different temperatures (723 K, 1023 K and 1323 K). The results reveal complex enrichment/depletion of each element depending on the alloy composition and temperature. Opposite segregation of Ni and Cr and co-segregation of Ni and Fe is observed for almost all compositions at 723 K, but a changing trend is observed with increasing temperature. We discuss the origin and consequences of these segregation behaviours in the light of magnetic ordering effects.
T2 - Materials Science and Engineering (MSE) 2024
CY - Darmstadt, Germany
DA - 24.09.2024
KW - Segregation
KW - Grain boundaries
KW - CALPHAD
PY - 2024
AN - OPUS4-62343
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kianinejad, Kaveh
A1 - Darvishi Kamachali, Reza
A1 - Khedkar, Abhinav
A1 - Manzoni, Anna Maria
A1 - Agudo Jácome, Leonardo
A1 - Schriever, Sina
A1 - Saliwan Neumann, Romeo
A1 - Megahed, Sandra
A1 - Heinze, Christoph
A1 - Kamrani, Sepideh
A1 - Fedelich, Bernard
T1 - Creep anisotropy of additively manufactured Inconel-738LC: Combined experiments and microstructure-based modeling
N2 - The current lack of quantitative knowledge on processing-microstructure–property relationships is one of the major bottlenecks in today’s rapidly expanding field of additive manufacturing. This is centrally rooted in the nature of the processing, leading to complex microstructural features. Experimentally-guided modeling can offer reliable solutions for the safe application of additively manufactured materials. In this work, we combine a set of systematic experiments and modeling to address creep anisotropy and its correlation with microstructural characteristics in laser-based powder bed fusion (PBF-LB/M) additively manufactured Inconel-738LC (IN738LC). Three sample orientations (with the tensile axis parallel, perpendicular, and 45° tilted, relative to the building direction) are crept at 850 °C, accompanied by electron backscatter secondary diffraction (EBSD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations. A crystal plasticity (CP) model for Ni-base superalloys, capable of modeling different types of slip systems, is developed and combined with various polycrystalline representative volume elements (RVEs) built on the experimental measurements. Besides our experiments, we verify our modeling framework on electron beam powder bed fusion (PBF-EB/M) additively manufactured Inconel-738LC. The results of our simulations show that while the crystallographic texture alone cannot explain the observed creep anisotropy, the superlattice extrinsic stacking faults (SESF) and related microtwinning slip systems play major roles as active deformation mechanisms. We confirm this using TEM investigations, revealing evidence of SESFs in crept specimens. We also show that the elongated grain morphology can result in higher creep rates, especially in the specimens with a tilted tensile axis.
KW - Additive manufactured Ni-base superalloys
KW - Creep
KW - Crystal plasticity
KW - Superlattice extrinsic stacking faults
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601576
DO - https://doi.org/10.1016/j.msea.2024.146690
SN - 0921-5093
VL - 907
SP - 1
EP - 16
PB - Elsevier B.V.
AN - OPUS4-60157
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Darvishi Kamachali, Reza
T1 - On the origin of embrittlement in Mn containing and Zn-coated steels
N2 - Grain boundary embrittlement in medium-Mn steels and liquid metal embrittlement (LME) in Zn-coated high strength steels are among key challenges on the way of safe application of sustainable steels for automotive industry. Using a novel density-based model for grain boundaries, we reveal that the affinity of a grain boundary to attract Mn and Zn atoms result in a segregation transition accompanied by interfacial structural changes. In case of the Zn, the simulations show that the amount of segregation abruptly increases with decreasing temperature, while the Zn content in the alloy, required for triggering the segregation transition, decreases. The results are discussed in the context of CALPHAD-integrated density-based grain boundary phase diagrams.
T2 - DPG 2024
CY - Berlin, Germany
DA - 17.03.2024
KW - Phase-Field Simulation
KW - CALPHAD
KW - Steels
KW - Density-based Thermodynamics
PY - 2024
AN - OPUS4-60743
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 - 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 - GEN
A1 - Ávila Calderón, Luis
A1 - Shakeel, Y.
A1 - Schriever, Sina
A1 - Gedsun, A.
A1 - Forti, M.
A1 - Jordan, Hans
A1 - Han, Ying
A1 - Baer, O.
A1 - Aversa, R.
A1 - Olbricht, Jürgen
A1 - Hammerschmidt, T.
A1 - Hickel, T.
A1 - Skrotzki, Birgit
T1 - NFDI-MatWerk/IUC02 Data schema for creep data of Ni-based superalloys including a comprehensive documentation of test results and metadata
N2 - This data schema was developed within the infrastructure use case IUC02: “Framework for curation and distribution of reference datasets” of the consortium NFDI-MatWerk. It intends to define a structured approach for collecting all required information on a creep experiment using the established terminology of the respective test standard ISO 204:2022 and additional terminology agreed upon by the domain experts. The individual entries are grouped according to their content type and sub-summarized under respective headlines, thereby suggesting a basic categorization and a related hierarchy of concepts. This hierarchy can be similarly applied to other test methods and different metallic (and other) materials.
In version 1.1 some editorial and formal changes were made.
KW - NFDI-MatWerk
KW - Digitalisierung
KW - Referenzdaten
KW - Kriechen
KW - Ni-based Superalloys
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611629
DO - https://doi.org/10.5281/zenodo.11668375
PB - Zenodo
CY - Geneva
AN - OPUS4-61162
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 - THES
A1 - Ávila Calderón, Luis
T1 - Mechanisches Verhalten von additiv gefertigtem nichtrostendem Stahl X2CrNiMo17-12-2 (AISI 316L) und Vergleich zur konventionell gefertigten Variante
T1 - Mechanical behavior of additively manufactured stainless steel X2CrNiMo17-12-2 (AISI 316L) and comparison with a conventionally manufactured variant
N2 - Die additive Fertigung (AM) metallischer Werkstoffe ist eine Technologie, die zunehmend Gegenstand von Forschungsaktivitäten und industrieller Anwendung ist. Dennoch steht sie noch vor Herausforderungen, um eine breite Nutzung in sicherheitsrelevanten Anwendungen zu erreichen. Die Hauptgründe für die Verzögerung des technologischen Durchbruchs zugunsten von AM-Metallen gegenüber konventionell hergestellten Varianten sind das Fehlen eines tieferen Verständnisses der Prozess-Struktur-Eigenschafts-Beziehungen und die begrenzte Verfügbarkeit von Daten zu den Materialeigenschaften. In diesem Kontext stellt diese Arbeit einen Beitrag sowohl zum Verständnis der Prozess-Struktur-Eigenschafts-Beziehungen als auch zur Verbesserung der Datenlage von 316L dar, einem häufig als Konstruktionswerkstoff in verschiedenen Hochtemperaturbauteilen verwendeten Werkstoff. Die Arbeit legt den Fokus auf die mittels Laser-Pulverbettschmelzen hergestellte Werkstoffvariante, PBF-LB/M/316L. Eine konventionell hergestellte Variante, HR/316L, wurde auch untersucht. Bei PBF-LB/M/316L wurde zusätzlich der Effekt ausgewählter Wärmebehandlungen ausgewertet. Die Untersuchung umfasste die Charakterisierung der mechanischen Eigenschaften und der Verformungs- und Schädigungsmechanismen bei erhöhten Prüftemperaturen bei LCF und Kriechen, wo die Daten und Wissenslage am spärlichsten ist. Außerdem hat die untersuchte PBF-LB/M/316L-Wersktoffvariante einen geringen Porositätsgrad. Somit hat diese Arbeit die Mikrostruktur stärker in den Fokus genommen als die meisten bisher in der Literatur verfügbaren Studien.
Die mechanische Prüfkampagne umfasste Zugversuche zwischen Raumtemperatur und 650 °C, LCF-Versuche zwischen Raumtemperatur und 600 °C sowie Kriechversuche bei 600 °C und 650 °C. In Ermangelung konkreter Richtlinien und Normen wurde die Charakterisierung zumeist anhand der bestehenden internationalen Prüfnormen und Probengeometrien durchgeführt. Aus jedem dieser Prüfverfahren wurden die entsprechenden Festigkeits- und Verformungskennwerte ermittelt. Darüber hinaus wurde mit Hilfe gezielter mikrostruktureller Untersuchungen ein Beitrag zum Verständnis des Zusammenhangs zwischen der Mikrostruktur und den mechanischen Eigenschaften in Bezug auf die Verformungs- und Schädigungsmechanismen geleistet.
Die Dehngrenze von PBF-LB/M/316L ist etwa doppelt so hoch wie die von HR/316L und dieser Trend setzt sich mit ansteigender Prüftemperatur fort. Die Bruchdehnung ist bei allen Prüftemperaturen geringer. PBF-LB/M/316L weist über den größten Teil der Ermüdungslebensdauer vor allem bei Raumtemperatur höhere zyklische Spannungen als HR/316L auf. Ausschließlich bei den kleinsten Dehnungs-schwingbreiten sind die Ermüdungslebensdauer ausgeprägt kürzer. Das Wechselverformungsverhalten von PBF-LB/M/316L ist durch eine Anfangsverfestigung gefolgt von einer kontinuierlichen Entfestigung charakterisiert, welche bis zum Auftreten der zum Versagen führenden Entfestigung stattfindet. Die Kriechbruchzeiten und die Dauer jeder Kriechphase sind bei allen Kombinationen von Prüfparametern bei PBF-LB/M/316 kürzer als bei HR/316L. Die Spannungsabhängigkeit von PBF-LB/M/316L ist im Vergleich zu HR/316L geringer und die Duktilität beim Kriechen kleiner. Die minimale Kriechrate wird bei allen geprüften Parameterkombinationen bei deutlich geringeren Kriechdehnungen erreicht. Eine Wärmebehandlung bei 450 °C / 4 h bewirkt keine wesentliche Änderungen der Mikrostruktur und Zugversuchseigenschaften. Eine zusätzliche Wärmebehandlung bei 900 °C / 1 h verursacht eine Abnahme der Dehngrenze des PBF-LB/M/316L. Diese blieb aber immer noch um den Faktor 1,5x höher als bei HR/316L. Die Verformungsmerkmale wurden kaum davon beeinflusst. Bezüglich des Kriechverhaltens hat die Wärmebehandlung bei 900 °C / 1 h längere sekundäre und tertiäre Kriechstadien bewirkt und die Kriechdehnung hat sich signifikant erhöht. Die Bruchbilder unterscheiden sich generell nicht nur aber vor allem mit ansteigender Prüftemperatur, bei der bei PBF-LB/M/316L oft interkristalline Rissbildung beobachtet wurde. Die Zellstruktur trägt als der Hauptfaktor zu den unterschiedlichen mechanischen Eigenschaften im Vergleich zur HR/316L-Variante bei. Darüber hinaus spielen mutmaßlich die Kornmorphologie, die Stapelfehlerenergie und der Stickstoffgehalt eine Rolle.
N2 - Metal additive manufacturing (AM) is a technology that is increasingly the subject of research activities and industrial applications. However, it still faces challenges to achieve widespread use in safety-relevant applications. The main reasons for the delay of this technological breakthrough in favor of AM metals over conventionally manufactured variants are the lack of a deeper understanding of process-structure-property relationships and the limited availability of data on material properties. In this context, this work contributes to both achieving a better understanding of process-structure-property relationships and the improvement of data for 316L, an alloy frequently used as a structural material in various high-temperature components. The work focuses on a material variant produced by laser pow-der bed fusion, PBF-LB/M/316L. A conventionally produced variant, HR/316L, was also investigated. For PBF-LB/M/316L, the effect of selected heat treatments was also evaluated. The investigation included the characterization of the mechanical properties and the related deformation and damage mechanisms at elevated test temperatures in LCF and creep, where data and knowledge are scarce. The PBF-LB/M/316L variant studied has a low degree of porosity. Thus, this work is more focused on the microstructure than most studies available in the literature.
The mechanical test campaign included tensile tests between room temperature and 650 °C, LCF tests between room temperature and 600 °C, and creep tests at 600 °C and 650 °C. In the absence of concrete guidelines and standards for testing of AM metals, the characterization mostly took place using existing international test standards and specimen geometries. From each of the test methods, corresponding strength, and deformation characteristic values were determined. In addition, targeted microstructural investigations contributed to understanding the relationship between the microstructure and the mechanical properties in terms of deformation and damage mechanisms.
The proof stress of PBF-LB/M/316L is about twice that of HR/316L. This trend remains with increasing test temperature. The elongation after fracture is lower at all test temperatures. Regarding LCF, PBF-LB/M/316L exhibits higher cyclic stresses than HR/316L for most of the fatigue life, especially at room temperature. Exclusively at the smallest strain amplitudes, the fatigue lives of PBF-LB/M/316L are markedly shorter than in HR/316L. The cyclic stress-strain deformation behavior of PBF-LB/M/316L features an initial strain hardening followed by a continuous softening, which occurs until the softening leading to failure takes place. The creep rupture times and the duration of each creep stage are shorter for PBF-LB/M/316 than for HR/316L for all combinations of test parameters. The stress dependence of PBF-LB/M/316L is lower, and the creep ductility is smaller compared to HR/316L. The minimum creep rate is reached at significantly lower creep extensions for all parameter combinations tested. A heat treatment at 450 °C / 4 h did not cause significant changes in the microstructure and tensile behavior. An additional heat treatment at 900 °C / 1 h caused a decrease in the proof stress of PBF-LB/M/316L. However, it still remained higher than the one of HR/316L by a factor of 1.5x. The deformation characteristics were hardly affected. Regarding the creep behavior, this latter heat treatment at 900 °C / 1 h caused longer secondary and tertiary creep stages, and the creep strain increased significantly. The fracture characteristics generally differed, which happened not only but especially with increasing test temperature, where intergranular cracking often took place in PBF-LB/M/316L. The cellular structure is considered the main factor contributing to the different mechanical properties compared to the HR/316L variant. In addition, grain morphology, stacking fault energy, and nitrogen content might play a role.
KW - AGIL
KW - Additive Fertigung
KW - Laser-Pulverbettschmelzen
KW - Mikrostrukturentwicklung
KW - 316L
KW - LCF
KW - Kriechen
KW - Additive Manufacturing
KW - Microstructure
KW - Mechanical Properties
KW - Mechanische Eigenschaften
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597143
DO - https://doi.org/10.14279/depositonce-19828
SP - 1
EP - 190
CY - Berlin
AN - OPUS4-59714
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ávila Calderón, Luis
T1 - Creep Behavior of Stainless Steel 316L Manufactured by Laser Powder Bed Fusion
N2 - This contribution presents the results of an experimental study on the creep behavior of an austenitic 316L stainless steel produced by laser powder bed fusion (PBF-LB/M/316L) with an emphasis on understanding the effects of microstructure on the creep mechanisms. Hot tensile tests and constant force creep tests at 600 °C and 650 °C, X-ray computed tomography, as well as optical and electron microscopy were performed. The produced PBF-LB/M/316L exhibits a low void population (< 0.01 %) resulting from the manufacturing parameters used and which allowed us to understand the effects of other microstructural aspects on creep behavior, e.g., grain morphology and dislocation substructure. A hot‑rolled variant of 316L was also tested as a reference.
T2 - International Materials Science and Engineering Congress - MSE 2024
CY - Darmstadt, Germany
DA - 24.09.2024
KW - AGIL
KW - Additive Fertigung
KW - Mikrostruktur
KW - Mikrostrukturentwicklung
KW - Kriechen
KW - Kriechschädigung
PY - 2024
AN - OPUS4-61169
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 - CONF
A1 - Bayerlein, Bernd
T1 - Digital Transformation in Materials Science:Insights from Platform MaterialDigital
N2 - In the digital transformation of materials science and engineering, existing processes are being closely examined to optimize and extend them using technologies such as the Semantic Web, while adhering to the FAIR principles. The challenge is to identify and adapt these technologies to significantly improve daily operations, covering the entire cycle of data generation, collection, storage to its processing and use. This presentation presents different approaches developed within the Platform MaterialDigital (PMD) and related initiatives, each addressing specific challenges of digitalization and demonstrating their benefits. These will be illustrated by a case study on age-hardenable aluminium alloys in different aging states, based on a comprehensive dataset of microstructural and mechanical properties.
In this context, ontologies are essential for organizing data into interoperable semantic structures, thereby enabling the representation of concepts and their relationships. The PMD Core Ontology (PMDco) serves as a higher semantic layer that connects domain-specific ontologies [1]. The PMDco provides MSE-specific bridging concepts that enhance data mapping and integration capabilities. This approach facilitates the linking of results from natural language processing of a corpus of microscopy abstracts, which supported the development of a microscopy ontology. In addition, the presentation highlights how modular, digital workflows can improve the reproducibility of transmission electron microscopy image processing and analysis [2]. It also shows how freely available mechanical and microstructural datasets are semantically integrated and made searchable through PMDco, facilitating correlation analysis [3]. Looking ahead, the integration of these components has the potential to advance and sustain MSE practices.
T2 - MSE Congress 2024 - Materials Science and Engineering
CY - Darmstadt, Germany
DA - 24.09.2024
KW - Semantic Interoperability
KW - FAIR data management
KW - Digtial Representation
PY - 2024
AN - OPUS4-61137
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Beygi Nasrabadi, Hossein
A1 - Skrotzki, Birgit
T1 - Tensile test ontology (TTO)
N2 - Tensile Test Ontology (TTO) has developed for representing the Tensile testing process, testing equipment requirements, test pieces charactristics, and related testing parameters and their measurement procedure according to DIN EN ISO 6892-1 standard.
Versions info:
V2 developed using BFO+CCO top-level ontologies.
V3 developed using PROVO+PMDco top-level ontologies.
Repositories:
GitLab: https://gitlab.com/kupferdigital/process-graphs/tensile-test
GitHub: https://github.com/HosseinBeygiNasrabadi/Tensile-Test-Ontology-TTO-
MatPortal: https://matportal.org/ontologies/TTO
IndustryPortal: https://industryportal.enit.fr/ontologies/TTO
KW - Ontology
KW - Tensile testing
PY - 2024
UR - https://gitlab.com/kupferdigital/process-graphs/tensile-test
UR - https://github.com/HosseinBeygiNasrabadi/Tensile-Test-Ontology-TTO-
UR - https://matportal.org/ontologies/TTO
UR - https://industryportal.enit.fr/ontologies/TTO
PB - GitLab
CY - San Francisco, CA, USA
AN - OPUS4-60545
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 - THES
A1 - Han, Ying
T1 - Hochtemperaturermüdung der Aluminiumlegierung EN AW-2618A
N2 - Abgasturbolader tragen wesentlich zur Effizienzsteigerung moderner Verbrennungsmotoren bei. Die im Abgasturbolader eingesetzten Radialverdichterräder werden überwiegend aus der warmfesten ausscheidungsgehärteten Aluminiumlegierung EN AW-2618A hergestellt.
Die Anforderungen an die Radialverdichterräder steigen und die Betriebszeiten verlängern sich. Für eine optimale Auslegung des Bauteils ist unter anderem die Kenntnis des Ermüdungsverhaltens dieser Legierung erforderlich. Es ist bekannt, dass sich die Mikrostruktur dieser Legierung während des Betriebs vergröbert und dadurch die Festigkeit abnimmt. Das niederzyklische Ermüdungsverhalten für den Ausgangszustand des Werkstoffs und Prüftemperaturen bis 190 °C ist bereits gut untersucht. Für das hochzyklische Ermüdungsverhalten, insbesondere für Prüftemperaturen über 190 °C, liegen jedoch nur wenige Ergebnisse vor. Das Ziel dieser Arbeit ist es daher, die Datenbasis hinsichtlich der hochzyklischen Ermüdungslebensdauer bei erhöhten Prüftemperatur zu vervollständigen und das Werkstoffverhalten sowie die Schädigungsmechanismen zu charakterisieren.
Zu diesem Zweck wurden axiale Ermüdungsversuche an glatten Proben durchgeführt.
Neben dem T61-Ausgangszustand für eine Basischarakterisierung wurden zwei überalterte Zustände, jeweils bei 230 °C für 10 h und 1000 h ausgelagert und anschließend geprüft, um den Einfluss der Überalterung auf die Ermüdungslebensdauer zu erfassen. Die Auslagerungstemperatur von 230 °C der überalterten Zustände liegt deutlich über der Aushärtungstemperatur von 195 °C des T61-Zustands, was zu Veränderungen der optimal eingestellten Mikrostruktur führt, die sich wiederum in den mechanischen Eigenschaften widerspiegeln. Mit der Überalterungszeit von 10 h wurde ein Zustand untersucht, der einem Härteniveau entspricht, der bei Bauteilrückläufern nach Langzeitbetrieb beobachtet wurde und mit der Überalterungszeit von 1000 h wurden die Werkstoffgrenzen ermittelt. Zusätzlich wurde mittels Transmissionselektronenmikroskopie (TEM) die Vergröberung der festigkeitssteigernden S-Phase untersucht. Der Einfluss der Prüftemperatur auf die Ermüdungslebensdauer wurde durch Versuche bei 230 °C untersucht. Die Ermüdungsversuche wurde durch fraktographische Untersuchungen ergänzt und ausgewählte Ermüdungsversuche wurden mit zerstörungsfreien Prüfmethoden begleitet, um die Schädigung mit zunehmender Zyklenzahl dazustellen.
Die Ergebnisse dieser Untersuchungen zeigen eine kürzere Ermüdungslebensdauer für die längere Überalterungszeit bei gleicher Spannungsamplitude. Die Transmissionselektronenmikroskopie zeigt, dass der mittlere Radius der S-Phase nach einer Überalterungszeit von 10 h um den Faktor 2,3 und nach 1000 h um den Faktor 2,7 im Vergleich zum Ausgangszustand zunimmt. Eine Erhöhung der Prüftemperatur auf 230 °C führt bei gleicher Spannungsamplitude zu einer Verkürzung der Ermüdungslebensdauer im Vergleich zu Raumtemperatur. Die fraktographischen Untersuchungen zeigen, dass unabhängig vom Werkstoffzustand und der Prüftemperatur die Rissinitiierung überwiegend an der Probenoberfläche oder in der Nähe der Primärphasen erfolgt. Das Risswachstum mit zunehmender Zyklenzahl kann mit der Replika-Methode erfolgreich abgebildet werden. Die
Abbildung des Risses in der noch nicht gebrochenen Probe ist auch mit der Computertomographie möglich.
KW - Aluminiumlegierung
KW - EN AW-2618A
KW - Ermüdung
KW - HCF
KW - Mikroskopie
KW - Fraktographie
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615288
DO - https://doi.org/10.14279/depositonce-21381
SP - 1
EP - 109
PB - Depostit Once
CY - Berlin
AN - OPUS4-61528
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Skrotzki, Birgit
T1 - Improving the Reproducibility of Characterization and Quantification of Precipitates through Automated Image Processing and Digital Representation of Processing Steps
N2 - The strength of age-hardenable aluminum alloys is based on the controlled formation of nm-sized precipitates, which represent obstacles to dislocation movement. Transmission electron microscopy (TEM) is generally used to identify precipitate types and orientations and to determine their size. This geometric quantification (e.g., length, diameter) is often performed by manual image analysis, which is very time consuming and sometimes poses reproducibility problems. The present work aims at the digital representation of this characterization method by proposing an automatable digital approach. Based on DF-TEM images of different precipitation states of alloy EN AW-2618A, a modularizable digital workflow is described for the quantitative analysis of precipitate dimensions. The integration of this workflow into a data pipeline concept is also presented. The semantic structuring of data allows data to be shared and reused for other applications and purposes, which enables interoperability.
T2 - ICAA19 International Conference on Aluminum Alloys
CY - Atlanta, GA, USA
DA - 23.06.2024
KW - Digital representation
KW - Automatable digital approach
KW - Digital workflow
KW - Quantitative image analysis
KW - Data pipeline concept
KW - Semantic structuring
KW - Interoperability
KW - FAIR data management
PY - 2024
AN - OPUS4-60427
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ávila Calderón, Luis
T1 - Microstructure Based Study on the Low Cycle Fatigue Behavior of Stainless Steel 316L manufactured by Laser Powder Bed Fusion
N2 - Due to the advantages of Laser Powder Bed Fusion (PBF-LB), i.e., design freedom and the possibility to manufacture parts with filigree structures, and the considerable amount of knowledge available for 316L in its conventional variant, the mechanical behavior, and related microstructure-property relationships of PBF-LB/316L are increasingly subject of research. However, many aspects regarding the - application-relevant - mechanical behavior at high temperatures are not yet fully understood. Here, we present the results of an experimental study on the LCF behavior of PBF-LB/316L featuring a low defect population, which makes this study more microstructure-focused than most of the studies in the literature. The LCF tests were performed between room temperature (RT) and 600 °C. The mechanical response is characterized by strain-life curves, and hysteresis and cyclic deformation curves. The damage and deformation mechanisms are studied with X-ray computed tomography, and optical and electron microscopy. The PBF-LB/M/316L was heat treated at 450 °C for 4 h, and a hot‑rolled (HR) 316L variant with a fully recrystallized equiaxed microstructure was tested as a reference. Besides, selected investigations were performed after a subsequent heat treatment at 900 °C for 1 h. The PBF-LB/316L exhibits higher cyclic stresses than HR/316L for most of the fatigue life, especially at room temperature. At the smallest strain amplitudes, the fatigue lives of PBF-LB/M/316L are markedly shorter than in HR/316L. The main damage mechanisms are multiple cracking at slip bands (RT) and intergranular cracking (600 °C). Neither the melt pool boundaries nor the gas porosity have a significant influence on the LCF damage mechanism. The cyclic stress-strain deformation behavior of PBF-LB/M/316L features an initial hardening followed by a continuous softening. The additional heat treatment at 900 °C for 1 h led to decreased cyclic stresses, and a longer fatigue life.
T2 - 4th Symposium on Materials and Additive Manufacturing
CY - Berlin, Germany
DA - 12.06.2024
KW - AGIL
KW - 316L
KW - Microstructure
KW - Low Cycle Fatigue
KW - Heat Treatment
KW - Laser Poeder Bed Fusion
PY - 2024
AN - OPUS4-60432
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 - CONF
A1 - Han, Ying
T1 - The influence of overaging on high cycle fatigue of Al-alloy EN AW-2618A
N2 - The aluminum alloy EN AW-2618A (2618A) is a precipitation hardened high strength alloy that is used at elevated temperatures in the transportation and aerospace industries. The main alloying elements are Cu and Mg which form a coarse intermetallic primary phase (Al9FeNi) of several µm in size. This phase is responsible for the long-term high temperature creep resistance. The basic strength is due to the precipitation of the so-called S-phase (Al2CuMg) of nm-size, which is known to coarsen during service at elevated temperatures.
Previous projects have characterized the alloy in terms of strength, low cycle fatigue (LCF) and creep behavior, especially at high temperatures (up to 190 °C). Both the T61 and overaged states were used. In addition, the microstructural changes associated with overaging were extensively studied and quantified microscopically [1-2].
However, data on high cycle fatigue (HCF) is still very limited. Therefore, this study [3] investigates the influence of overaging on HCF of 2618A. For this purpose, axial HCF tests were performed at room temperature on two overaged states which are aged for 10 h and 1000 h at 230 °C. Electron microscopy was used to characterize the coarsening of the S-phase from the two overaged states. Fractographic studies were also performed to investigate the influence of the primary phase on the fatigue life.
T2 - MSE 2024
CY - Darmstadt, Germany
DA - 24.09.2024
KW - Fatigue
KW - Aluminum alloy
KW - EN AW-2618A
PY - 2024
AN - OPUS4-61188
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schilling, Markus
T1 - Transforming Materials Science with ontologies, ELN, and LIMS: Semantic Web Solutions for Digitalization and Data Excellence
N2 - Following the new paradigm of materials development, design and optimization, digitalization is the main goal in materials sciences (MS) which imposes a huge challenge. In this respect, the quality assurance of processes and output data as well as the interoperability between applications following FAIR (findability, accessibility, interoperability, reusability) principles are to be ensured. For storage, processing, and querying of data in contextualized form, Semantic Web Technologies (SWT) are used since they allow for machine-understandable and human-readable knowledge representations needed for data management, retrieval, and (re)use.
The project ‘platform MaterialDigital’ (PMD) is part of an initiative that aims to bring together and support interested parties from both industrial and academic sectors in a sustainable manner in solving digitalization tasks and implementing digital solutions. Therefore, the establishment of a virtual material data space and the systematization of the handling of hierarchical, process-dependent material data are focused. Core points to be dealt with are the development of agreements on data structures and interfaces implemented in distinct software tools and to offer users specific added values in their projects. Furthermore, the platform contributes to a standardized description of data processing methods in materials research. In this respect, selected MSE methods are ontologically represented which are supposed to serve as best practice examples with respect to knowledge representation and the creation of knowledge graphs used for material data.
Accordingly, this presentation shows the efforts taken within the PMD project to store data in accordance with a testing standard compliant ontological representation of a tensile test of metals at room temperature (ISO 6892-1:2019-11). This includes the path from developing an ontology in accordance with the respective standard up to connecting the ontology and data. The semantic connection of the ontology and data leads to interoperability and an enhanced ability of querying. For further enhanced reusability of data and knowledge from synthesis, production, and characterization of materials, the PMD core ontology (PMDco) was developed as mid-level ontology in the field of MSE. The semantic connection of the tensile test ontology (TTO) to the PMDco leads to enhanced expressivity and interoperability.
Moreover, as a best practice example, generation and acquisition of test data semantically connected to the ontology (data mapping) was realized by applying an electronic laboratory notebook (ELN). Corresponding tensile tests were performed by materials science students at university. This enabled a fully digitally integrated experimental procedure that can be transferred to other test series and experiments. In addition to facilitating the acquisition, analysis, processing, and (re)usability of data, this also raises the awareness of students with respect to data structuring and semantic technologies in the sense of education and training. The entire data pipeline is further seamlessly integrable in a laboratory information management system (LIMS). More specifically, the integration of semantic conceptualization and knowledge graphs may become essential parts in LIMS as this would be very beneficial. Therefore, some first approaches of SWT integration in LIMS will also be presented briefly.
T2 - TMS Specialty Congress 2024
CY - Cleveland, OH, USA
DA - 16.06.2024
KW - Semantic Data
KW - Plattform Material Digital
KW - Tensile Test Ontology
KW - Electronic Lab Notebook
KW - Material Life Cycle
PY - 2024
AN - OPUS4-60394
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Beygi Nasrabadi, Hossein
A1 - Skrotzki, Birgit
T1 - Tensile stress relaxation test ontology (TSRTO)
N2 - Tensile Stress Relaxation Test Ontology (TSRTO) has developed for representing the tensile stress relaxation testing process, testing equipment requirements, test pieces charactristics, and related testing parameters and their measurement procedure according to DIN EN ISO 10319-1 standard.
Versions info:
V1 developed using BFO+CCO top-level ontologies.
V3 developed using PROV+PMDco top-level ontologies.
Repositories:
GitLab: https://gitlab.com/kupferdigital/process-graphs/relaxation-test
GitHub: https://github.com/HosseinBeygiNasrabadi/Tensile-Stress-Relaxation-Test-Ontology-TSRTO
MatPortal: https://matportal.org/ontologies/TSRTO
IndustryPortal: https://industryportal.enit.fr/ontologies/TSRTO
KW - Ontology
KW - Tensile stress relaxation testing
KW - FAIR data
PY - 2024
UR - https://gitlab.com/kupferdigital/process-graphs/relaxation-test
UR - https://github.com/HosseinBeygiNasrabadi/Tensile-Stress-Relaxation-Test-Ontology-TSRTO
UR - https://matportal.org/ontologies/TSRTO
UR - https://industryportal.enit.fr/ontologies/TSRTO
PB - GitLab
CY - San Francisco, CA, USA
AN - OPUS4-60546
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ávila Calderón, Luis
T1 - Research Data Management for Creep Reference Data of Ni Based Superalloys
N2 - In times of digital data processing and sharing, a central challenge for the Materials Science and Engineering (MSE) community is the complete digital representation of materials, including their relevant processing and microstructure details and the resulting properties. This digital representation, supported by digital infrastructures, enables entirely new qualities of collaborative work and is central to how we will conduct MSE research and develop products in the future. The main challenges are the composition, shaping, and description of the data so that it can be easily interpreted, trusted, and re-used. This presentation introduces our current effort to develop a best practice framework for generating and distributing creep reference datasets for Ni-based superalloys, which builds on previous approaches. Researchers can use such datasets to compare their own experimental or simulation results, used, for instance, to perform simulation-based alloy design and optimization or in the verification of the own testing equipment. The concept includes building an easily accessible digital infrastructure to annotate and discover the datasets and the integration of an ontology that aligns with the necessary metadata schema. With the help of an ontology, the reference dataset for creep can be semantically described, thus enabling the digital representation and reusage of shared concepts from domain experts and the community. To achieve this, it is necessary to establish a defined vocabulary with corresponding relations and annotations. The interplay between a digital infrastructure, the agreement on the necessary metadata and related metadata schema, and an underlying ontology will ensure that data and results can be easily shared, taken up, and re-used, thus fulfilling the FAIR principles (Findable, Accessible, Interoperable, Reusable). Furthermore, we aim to develop a widely accepted definition of reference data and data quality levels and to reach a self-supported community process. We intend to motivate the discussion about reference material datasets, necessary metadata, and future collaborations within the creep community.
T2 - 16th International Conference on Creep and Fracture of Engineering Materials and Structures
CY - Bangalore, India
DA - 28.07.2024
KW - Reference Data
KW - Creep
KW - Data schema
KW - Research Data Management
PY - 2024
AN - OPUS4-60837
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 -