TY - GEN A1 - Skrotzki, Birgit A1 - Schriever, Sina T1 - BAM reference data - Results of ASTM E139-11 creep tests on a reference material of Nimonic 75 nickel-base alloy N2 - Results of creep tests on a certified reference material at T = 600°C and a tensile creep load of 160 MPa are provided. The evaluated results include the times to reach 2% and 4% creep strain, respectively, and the creep rate after 400 h. The data were audited and are BAM reference data. KW - Reference data KW - Creep KW - Nickel-base alloy KW - Nimonic 75 KW - Reference material BCR-425 PY - 2021 DO - https://doi.org/10.5281/zenodo.5106606 PB - Zenodo CY - Geneva AN - OPUS4-52970 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - Tensile Test Ontology used in Platform Material Digital (PMD) N2 - Data analysis methods play an important role in both the experimental and simulation-based digital description of materials but have so far been poorly structured. The platform Material Digital (PMD) is supposed to contribute to a standardized description of data processing methods in materials research. The goal is the quality assurance of the processes and the output data, the acquisition and definition of their accuracy as well as the interoperability between applications. Therefore, application ontologies are created to explicitly describe processes and test methods. In this presentation, the first efforts within the joint project PMD in creating a tensile test application ontology in accordance with the ISO standard 6892-1:2019-11 are shown. Especially, the path of ontology development to be pursued based on standards was focused. Furthermore, the presentation includes a live demonstration of queries possibly performed to query data that was uploaded in the PMD triple store. T2 - Online Workshop: An introduction to the semantic web and ontologies CY - Online meeting DA - 23.04.2021 KW - Ontology KW - Tensile Test KW - Platform Material Digital KW - PMD KW - Knowledge Graphs KW - Semantic Web PY - 2021 AN - OPUS4-52949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Manzoni, Anna Maria A1 - Haas, S. A1 - Glatzel, U. T1 - Tuning high entropy alloys towards superalloy applications N2 - The discovery of the high entropy concept at the beginning of the 3rd millennium lead to a worldwide increase in metallurgical research, as the possible element combinations seemed nearly endless and the range of applications wide. In the early years of research, one of the main goals was the discovery of a single-phase high entropy alloy. As research evolved, it was found that properties could be enhanced by opening the HE-concept towards multiphase alloys, and from the wide area of possibilities our group chose a tuning of the properties towards high temperature application. Compositionally complex Al10Co25Cr8Fe15Ni36Ti6 alloy, which is single-phase at high temperature, around 1200°C, shows a three phase morphology at intermediate temperatures, around 800°C. A high temperature homogenization procedure has to be applied in order to decrease the segregation induced by the dendritic growth. Subsequent annealing promotes the formation of the strengthening γ' precipitates. The alloy shows a positive lattice misfit between the γ and the γ' phase, which can be an indicator for good creep properties. The microstructure can be optimized by adding trace elements such as Mo and Hf, known as γ and γ' strengtheners in Ni-based superalloys, respectively. Atom probe measurements show that Mo segregates into the γ matrix, and Hf prefers the γ' precipitates, where it increases the lattice parameter and thus also the lattice misfit, by about 50%. The alloy family shows interesting mechanical properties, especially the Al9.5Co25Cr8Fe15Ni36Ti6Hf0,5 alloy – its tensile properties are better than those of commercial Alloy 800H and IN617 at temperatures up to 700°C. T2 - BAM Abteilungsseminar CY - Online meeting DA - 21.01.2021 KW - High entropy alloys KW - Compositionally complex alloys KW - Superalloys KW - Hochentropie-Legierung KW - Legierung mit komplexer Zusammensetzung KW - Superlegierung PY - 2021 AN - OPUS4-52442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhou, X. A1 - Darvishi Kamachali, Reza A1 - Boyce, B.L. A1 - Clark, B.G. A1 - Raabe, D. A1 - Thompson, G.B. T1 - Spinodal Decomposition in Nanocrystalline Alloys N2 - For more than half a century, spinodal decomposition has been a key phenomenon in considering the formation of secondary phases in alloys. The most prominent aspect of the spinodal phenomenon is the lack of an energy barrier on its transformation pathway, offering an alternative to the nucleation and growth mechanism. The classical description of spinodal decomposition often neglects the influence of defects, such as grain boundaries, on the transformation because the innate ability for like-atoms to cluster is assumed to lead the process. Nevertheless, in nanocrystalline alloys, with a high population of grain boundaries with diverse characters, the structurally heterogeneous landscape can greatly influence the chemical decomposition behavior. Combining atom-probe tomography, precession electron diffraction and density-based phase-field simulations, we address how grain boundaries contribute to the temporal evolution of chemical decomposition within the miscibility gap of a Pt-Au nanocrystalline system. We found that grain boundaries can actually have their own miscibility gaps profoundly altering the spinodal decomposition in nanocrystalline alloys. A complex realm of multiple interfacial states, ranging from competitive grain boundary segregation to barrier-free low-dimensional interfacial decomposition, occurs with a dependency upon the grain boundary character. KW - Density-based Thermodynamics KW - Nanocrystalline alloys KW - Spinodal decomposition KW - Defects engineering PY - 2021 DO - https://doi.org/10.1016/j.actamat.2021.117054 VL - 215 SP - 117054 PB - Elsevier Ltd. AN - OPUS4-52918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Charmi, Amir T1 - Mechanical anisotropy of LPBF 316L: a modeling approach N2 - The underlying cause of mechanical anisotropy in additively manufactured (AM) parts is not yet fully understood and has been attributed to several different factors like microstructural defects, residual stresses, melt pool boundaries, crystallographic and morphological textures. To better understand the main contributing factor to the mechanical anisotropy of AM stainless steel 316L, bulk specimens were fabricated via laser powder bed fusion (LPBF). Tensile specimens were machined from these AM bulk materials for three different inclinations relative to the build plate. Dynamic Young's modulus measurements and tensile tests were used to determine the mechanical anisotropy. Some tensile specimens were also subjected to residual stress measurement via neutron diffraction, porosity determination with X-ray micro-computed tomography, and texture analysis with electron backscatter diffraction (EBSD). A crystal plasticity model was used to analyze the elastic anisotropy and the anisotropic yield behavior of the AM specimens, and it was able to capture and predict the experimental behavior accurately. Overall, it was shown that the mechanical anisotropy of the tested specimens was mainly influenced by the crystallographic texture. T2 - 2. Online-Workshop "In-situ Monitoring and Microstructure Development in Additive Manufactured Alloys " CY - Online meeting DA - 20.04.2021 KW - Anisotropy KW - Crystal plasticity KW - Additive manufacturing PY - 2021 AN - OPUS4-52603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ávila Calderón, Luis Alexander T1 - Creep behavior and microstructural evolution of LPBF 316L N2 - This presentation shows some experimental results of the characterization of the creep behavior of LPBF 316L, which has been poorly studied and understood to date. The presentation includes results regarding the mechanical properties, the initial microstructural state and its evolution under loading, and the damage mechanism. This work was done within the BAM focus area materials project AGIL. As a benchmark to assess the material properties of the LPBF 316L, a conventionally manufactured variant was also tested. T2 - 2nd Workshop on In-situ Monitoring and Microstructure Development in Additive Manufactured alloys at BAM CY - Online Meeting DA - 19.04.2021 KW - 316L KW - Additive Manufacturing KW - Creep behavior PY - 2021 AN - OPUS4-52682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, A. A1 - Camin, B. A1 - Hansen, L. A1 - Heuser, M. A1 - Lopez-Galilea, I. A1 - Ruttert, B. A1 - Theisen, W. A1 - Fedelich, Bernard T1 - Refinement and Experimental Validation of a Vacancy Model of Pore Annihilation in Single-Crystal Nickel-Base Superalloys during Hot Isostatic Pressing N2 - Initially, as-cast and homogenized single crystals of nickel-base superalloy CMSX-4 are subjected to hot isostatic pressing at 1288 °C. Two series of experiments are conducted: under the same pressure of 103 MPa but with different durations, between 0.5 and 6 h, and under different pressures, between 15 and 150 MPa, but for the same time of 0.5 h. The porosity annihilation is investigated metallographically and by high-resolution synchrotron X-ray tomography. The obtained experimental results are compared with the predictions of the vacancy model proposed recently in the group. Herein, the model is further refined by coupling with X-ray tomography. The model describes the evolution of the pore arrays enclosed in the 3D synchrotron tomograms during hot isostatic pressing and properly predicts the time and stress dependences of the pore annihilation kinetics. The validated model and the obtained experimental results are used for selecting the optimal technological parameters such as applied pressure and processing time KW - Superalloys KW - HIP KW - Single-Crystal KW - Diffusion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526859 DO - https://doi.org/10.1002/adem.202100211 VL - 23 IS - 7 SP - 211 AN - OPUS4-52685 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishurova, Tatiana A1 - Artzt, K. A1 - Rehmer, Birgit A1 - Haubrich, J. A1 - Avila, Luis A1 - Schoenstein, F. A1 - Serrano Munoz, Itziar A1 - Requena, G. A1 - Bruno, Giovanni T1 - Separation of the impact of residual stress and microstructure on the fatigue performance of LPBF Ti-6Al-4V at elevated temperature N2 - Manufacturing defects, high residual stress (RS), and microstructures affect the structural integrity of laser powder bed fusion (LPBF) Ti-6Al-4V. In this study, the individual effect of these factors on fatigue performance at elevated temperature (300 °C) was evaluated. Material in as-built condition and subjected to post-processing, including two heat treatments and hot isostatic pressing, was investigated. It was found that in the absence of tensile RS, the fatigue life at elevated temperature is primary controlled by the defects; and densification has a much stronger effect than the considered heat treatments on the improvement of the mechanical performance. KW - Additive manufacturing KW - Ti-6Al-4V KW - Residual stress KW - Fatigue performance KW - Computed tomography PY - 2021 DO - https://doi.org/10.1016/j.ijfatigue.2021.106239 SN - 0142-1123 VL - 148 SP - 106239 PB - Elsevier Ltd. AN - OPUS4-52369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jürgens, Maria A1 - Sonntag, Nadja A1 - Olbricht, Jürgen A1 - Fedelich, Bernard A1 - Skrotzki, Birgit T1 - The effect of dwell times on the thermomechanical fatigue life performance of grade P92 steel at intermediate and low strain amplitudes N2 - Results of an extended TMF test program on grade P92 steel in the temperature range of 620 °C - 300 °C, comprising in-phase (IP) and out-of-phase (OP) tests, partly performed with symmetric dwells at Tmax/Tmin, are presented. In contrast to previous studies, the low-strain regime is also illuminated, which approaches flexible operation in a power plant with start/stop cycles. At all strain amplitudes, the material performance is characterized by continuous cyclic softening, which is retarded in tests at lower strains but reaches similar magnitudes in the course of testing. In the investigated temperature range, the phase angle does not affect fatigue life in continuous experiments, whereas the IP condition is more detrimental in tests with dwells. Fractographic analyses indicate creep-dominated and fatigue-dominated damage for IP and OP, respectively. Analyses of the (micro)hardness distribution in the tested specimens suggest an enhanced microstructural softening in tests with dwell times for the low- but not for the high-strain regime. To rationalize the obtained fatigue data, the fracture-mechanics-based D_TMF concept, which was developed for TMF life assessment of ductile alloys, was applied. It is found that the D_TMF parameter correlates well with the measured fatigue lives, suggesting that subcritical growth of cracks (with sizes from a few microns to a few millimeters) governs failure in the investigated range of strain amplitudes. KW - 9-12%Cr steel KW - Thermomechanical fatigue KW - Symmetric dwell periods KW - Low strain KW - Parametric modeling PY - 2021 DO - https://doi.org/10.1016/j.msea.2020.140593 VL - 805 SP - 140593 PB - Elsevier B.V. AN - OPUS4-52374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ganesh, Rahul A1 - Gesell, Stephan A1 - Kuna, M. A1 - Fedelich, Bernard A1 - Kiefer, B. T1 - Numerical calculation of ΔCTOD for thermomechanical fatigue crack growth N2 - The cyclic crack tip opening displacement ΔCTOD is a promising loading Parameter to quantify the crack propagation under thermomechanical fatigue (TMF). In this work, suitable techniques are investigated and compared for an accurate calculation of ΔCTOD under TMF loading using a viscoplastic temperature dependent material model. It turned out that collapsed special crack tip elements give the best results. An efficient FEM-technique is developed to simulate the incremental crack growth by successive remeshing, whereby the deformations and internal state variables are mapped from the old mesh onto the new one. The developed techniques are demonstrated and discussed for two-dimensional examples like TMF-specimens. Recommendations are made regarding important numerical control parameters like optimal size of crack tip elements, length of crack growth increment in relation to plastic zone size and ΔCTOD value. N2 - Zur Bewertung des Rissfortschritts unter thermomechanischer Ermüdung (TMF) ist die zyklische Rissöffnungsverschiebung ΔCTOD ein aussichtsreicher bruchmechanischer Beanspruchungsparameter. In dieser Arbeit werden unter Anwendung eines viskoplastischen, temperaturabhängigen Materialmodells geeignete FEM-Techniken für die akkurate Berechnung des ΔCTOD bei TMF erprobt und verglichen. Als beste Technik hat sich die Verwendung kollabierter Rissspitzenelemente erwiesen. Es wurde ein effizienter FEM-Algorithmus zur Simulation der Rissausbreitung mit inkrementeller Neuvernetzung entwickelt, bei dem die Verformungen und inelastischen Zustandsvariablen jeweils vom alten auf das neue Netz übertragen werden. Die erarbeiteten Techniken werden am Beispiel von zweidimensionalen Strukturen und TMF-Proben vorgestellt und diskutiert. Dabei werden wesentliche Kontrollparameter der Simulation wie optimale Grösse der Rissspitzenelemente, Länge des Rissinkrementes in Relation zur plastischen Zone und dem ΔCTOD-Wert empfohlen. T2 - 53. Tagung des Arbeitskreises "Bruchmechanik und Bauteilsicherheit" CY - Online meeting DA - 18.02.2021 KW - Crack tip opening displacement KW - Thermomechanical fatigue KW - Crack growth PY - 2021 SP - 1 EP - 10 PB - DVM (Deutscher Verband für Materialforschung und -prüfung) CY - Berlin AN - OPUS4-52519 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ganesh, Rahul A1 - Gesell, Stephan A1 - Kuna, M. A1 - Fedelich, Bernard A1 - Kiefer, B. T1 - Numerical calculation of ΔCTOD for thermomechanical fatigue crack growth N2 - The cyclic crack tip opening displacement ΔCTOD is a promising loading Parameter to quantify the crack propagation under thermomechanical fatigue (TMF). In this work, suitable techniques are investigated and compared for an accurate calculation of ΔCTOD under TMF loading using a viscoplastic temperature dependent material model. It turned out that collapsed special crack tip elements give the best results. An efficient FEM-technique is developed to simulate the incremental crack growth by successive remeshing, whereby the deformations and internal state variables are mapped from the old mesh onto the new one. The developed techniques are demonstrated and discussed for two-dimensional examples like TMF-specimens. Recommendations are made regarding important numerical control parameters like optimal size of crack tip elements, length of crack growth increment in relation to plastic zone size and ΔCTOD value. T2 - 53. Tagung des Arbeitskreises "Bruchmechanik und Bauteilsicherheit" CY - Online meeting DA - 18.02.2021 KW - Crack tip opening displacement KW - Thermomechanical fatigue KW - Crack growth PY - 2021 AN - OPUS4-52520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gesell, Stephan A1 - Ganesh, Rahul A1 - Kuna, Meinhard A1 - Fedelich, Bernard A1 - Kiefer, Björn T1 - Numerical calculation of ΔCTOD for thermomechanical fatigue crack growth N2 - The cyclic crack tip opening displacement ΔCTOD is a promising loading Parameter to quantify the crack propagation under thermomechanical fatigue (TMF). In this work, suitable techniques are investigated and compared for an accurate calculation of ΔCTOD under TMF loading using a viscoplastic temperature dependent material model. It turned out that collapsed special crack tip elements give the best results. An efficient FEM-technique is developed to simulate the incremental crack growth by successive remeshing, whereby the deformations and internal state variables are mapped from the old mesh onto the new one. The developed techniques are demonstrated and discussed for two-dimensional examples like TMF-specimens. Recommendations are made regarding important numerical control parameters like optimal size of crack tip elements, length of crack growth increment in relation to plastic zone size and ΔCTOD value. T2 - ESIS Technical Meeting on Numerical Methods (TC8) CY - Online meeting DA - 06.04.2021 KW - Crack tip opening displacement KW - Thermomechanical fatigue KW - Crack growth PY - 2021 AN - OPUS4-52410 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wang, Lei A1 - Darvishi Kamachali, Reza T1 - Density-based Thermodynamics of Microstructure Defects N2 - Systematic microstructure design requires reliable thermodynamic descriptions and phase diagrams of each and all microstructure elements. While such descriptions are well established for most bulk phases, thermodynamic assessment of crystal defects is greatly challenged by their individualistic aspects. In this talk, we present a density-based thermodynamic concept to describe defects based on available bulk thermodynamic data. Here dealing with grain boundaries (GBs), we apply this concept to compute GB (phase) diagram. Applications to segregation engineering of GBs in bulk and nanocrystalline alloys will be presented. We further develop this model to include the effect of elastic interactions due to atom size mismatch and obtain the corresponding GB (phase) diagram for the ternary Al-Cu-Li system. T2 - TMS 2021 CY - Online meeting DA - 15.03.2021 KW - Microstrucrue Design KW - Density-based Thermodynamics PY - 2021 AN - OPUS4-52337 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Darvishi Kamachali, Reza T1 - Interfacial Spinodals N2 - Despite their finite spatial extent, interfaces can have profound impacts on microstructure properties. This is because of their distinct phase-like properties distinguishing them from the adjacent homogeneous bulk structure. When noticed by solute atoms, interfaces can experience their own chemical phase changes. In this talk, we investigate the constrained states of chemically decomposed phases at interfaces. A density-based theory of interfaces is proposed to describe the confined chemical decomposition at general grain boundaries. Here the grain boundary is viewed as a lesser dense, defected structure with reference to the corresponding bulk structure. Using this picture, the thermodynamic origins of interfacial spinodal phenomena are revealed. We also show that transient interfacial spinodals can be activated over a large alloy composition range, enabling kinetic engineering of interfacial chemistry. T2 - TMS 2021 CY - Online meeting DA - 15.03.2021 KW - Microstrucrue Design KW - Spinodal Decomposition KW - Interfacial Spinodal PY - 2021 AN - OPUS4-52338 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Lei A1 - Hoyt, J. J. T1 - Layering misalignment and negative temperature dependence of interfacial free energy of B2-liquid interfaces in a glass forming system N2 - From molecular dynamics simulations and the capillary fluctuation method, the solid-liquid interfacial free energy has been computed for the B2-liquid interface in the Cu-Zr system. Consistent with previous results for the FCC-liquid interface in Cu-Zr and Al-Sm but atypical of most alloys, was found to increase as the temperature is lowered. In addition, the temperature dependence was obtained for model Lennard-Jones B2-liquid alloys. In all cases the unusual temperature dependence of is correlated with an atomic structure of the interfacial region characterized by a misalignment of the number density peaks between solvents and solutes. In cases where the number density peaks are aligned, the typical temperature dependence is observed. The results are discussed in terms of the Gibbs theory of the thermodynamics of interfaces. It is proposed that the unique interfacial structure and the atypical temperature dependence of are hallmarks of an easy glass forming alloy. KW - Atomistic simulations KW - Interfacial free energy KW - Layering misalignment KW - Glass forming PY - 2021 DO - https://doi.org/10.1016/j.actamat.2021.117259 SN - 1359-6454 VL - 219 SP - 117259 PB - Elsevier Ltd. AN - OPUS4-53650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abel, Andreas A1 - Zapala, P. A1 - Michels, H. A1 - Skrotzki, Birgit T1 - Microstructure-Property-Correlation of a Mo-Ti-B alloyed iron aluminide N2 - Iron aluminides depict a sustainable and light-weight material class which could be employed in many applications requiring high strength at intermediate to high temperatures. According to first results, the alloy Fe-26Al-4Mo-0.5Ti-1B surpasses conventional materials in wet corrosion resistance and creep resistance up to 650 °C. For these reasons, the AiF research project “WAFEAL – Materials applications for iron aluminides” was initiated to transfer these findings into a standardised materials dataset and to derive best practices for processing. In the first place, a set of different microstructures adjusted by varying casting methods, wall thicknesses and heat treatments was investigated and correlated with hardness on macro and micro scale. Correlations were drawn between solidification rates and resulting grain sizes and hardness. The effect of vacancy hardening was only verified for wall thickness as low as 2.5 mm. Moreover, a common decrease of macrohardness after a heat treatment at 1000 °C for 100 h was observed irrespective of casting process or wall thickness. This effect was linked with an unexpected decrease of the complex boride phase fraction which acts as a hardening phase. T2 - Intermetallics 2021 CY - Bad Staffelstein, Germany DA - 04.10.2021 KW - Fe-Al alloys KW - Intermetallics KW - Iron aluminides KW - Heat treatment KW - Wall thickness KW - Centrifugal casting KW - Die casting KW - Investment casting KW - Microstructure KW - Hardness KW - Complex borides PY - 2021 AN - OPUS4-53617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus A1 - Skrotzki, Birgit A1 - Olbricht, Jürgen T1 - Ansätze zur digitalen Wissensrepräsentation aus der Plattform MaterialDigital (PMD) N2 - Die Digitalisierung von Materialien und Prozessen stellt eine große Herausforderung dar, die nur durch eine Bündelung der Bemühungen aller Beteiligten in diesem Bereich erreicht werden kann. Bei einer derartigen digitalen Beschreibung spielen Datenanalysemethoden, eine Qualitätssicherung von Prozessen inklusive Input- und Output-Daten sowie die Interoperabilität zwischen Anwendungen nach den FAIR-Prinzipien eine wichtige Rolle. Dies umfasst das Speichern, Verarbeiten und Abfragen von Daten in einer vorzugsweise standardisierten Form (Beteiligung von Normungsgremien). Zur Bewältigung dieser Herausforderung ist eine mit allen Stakeholdern konsistente Kontextualisierung der Materialdaten anzustreben, d.h. alle erforderlichen Informationen über den Zustand des Materials einschließlich produktions- und anwendungsbezogener Änderungen müssen über eine einheitliche, maschinenlesbare Beschreibung verfügbar gemacht werden. Dazu werden Wissensrepräsentationen und Konzeptualisierungen ermöglichende Ontologien verwendet. Eine zentrale Betrachtungsweise in diesem Zusammenhang ist die Realisierung von (automatisierten) Datenpipelines, die eine Beschreibung und Verfolgung von Daten ausgehend von ihrer Erzeugung, bspw. in einem Messgerät, bis zu ihrer globalen Verwendung in möglicherweise verschiedenen Kontexten beinhalten. Erste Bemühungen und Ansätze zu diesen Problemstellungen führten im Projekt Innovations-Plattform Material Digital (PMD, materialdigital.de) zur Erstellung von Anwendungsontologien, die Prozesse und Testmethoden explizit beschreiben. Dabei wurde u.a. der Zugversuch an Metallen bei Raumtemperatur nach ISO 6892-1 ontologisch beschrieben. Diese als Beispiel dienende Ontologieentwicklung wird in dieser Präsentation vorgestellt. Weiterhin wurde, ausgehend von der domänenspezifischen Entwicklung von Anwendungsontologien, eine Kernontologie erstellt, die eine übergeordnete Verbindung von ontologischen Konzepten aufgrund der Verwendung gleichen Vokabulars und semantischer Verknüpfungen erlaubt. Diese sowie die das PMD-Projekt selbst werden ebenfalls in dieser Präsentation vorgestellt. T2 - DVM Workshop: Grundlagen und Beispiele zur Digitalisierung für die Materialforschung und -prüfung CY - Online meeting DA - 19.10.2021 KW - Plattform Material Digital (PMD) KW - Ontologie KW - Zugversuch KW - Wissensrepräsentation KW - Semantic Web PY - 2021 AN - OPUS4-53565 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Darvishi Kamachali, Reza A1 - Wang, Lei A1 - Lin, L. L. A1 - Manzoni, Anna Maria A1 - Skrotzki, Birgit A1 - Thompson, G. B. T1 - CALPHAD-informed density-based grain boundary thermodynamics N2 - The Gibbs free energy of a grain boundary is a complex thermodynamic function of temperature, pressure, and composition. These complexities add to the intrinsic crystallographic and chemical constraints imposed by the adjacent bulk phase. Recently we have proposed a density-based model for assessing grain boundary thermodynamics that enables a CALPHAD-informed description of the grain boundary. As such, the Gibbs free energy of the grain boundary is directly linked with available CALPHAD thermodynamic data. In this talk, new aspects of interfacial segregation and phase transformation are revealed by benchmarking the current model for various experimental cases, including several steels, high-entropy alloys and aluminum alloys. The effects of elastic interactions on the grain boundary segregation and the application of the model to a nanocrystalline Pt-Au alloy, with numerous grain boundaries of various characters, will be discussed. T2 - DPG (Deutsche Physiker Gesellschaft) CY - Online meeting DA - 27.09.2021 KW - Density-based model KW - Defects thermodynamics KW - Defects phase diagram KW - CALPHAD KW - Crystal Defects PY - 2021 AN - OPUS4-53556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayerlein, Bernd A1 - Schilling, Markus A1 - Olbricht, Jürgen A1 - Skrotzki, Birgit A1 - Portella, Pedro Dolabella A1 - Hartrott, P. A1 - Hadzic, N. A1 - Todor, A. A1 - Birkholz, H. A1 - Grundmann, J. T1 - Digitalisierung der Materialien in PMD & Mat-o-Lab - Eine normkonforme Anwendungsontologie des Zugversuchs N2 - Zur Bewältigung der Herausforderung bei der Digitalisierung von Materialien und Prozessen ist eine mit allen Stakeholdern konsistente Kontextualisierung von Materialdaten anzustreben, d.h. alle erforderlichen Informationen über den Zustand des Materials einschließlich produktions- und anwendungsbezogener Änderungen müssen über eine einheitliche, maschinenlesbare Beschreibung verfügbar gemacht werden. Dazu werden Wissensrepräsentationen und Konzeptualisierungen ermöglichende Ontologien verwendet. Erste Bemühungen in den beiden Projekten Plattform Material Digital und Materials-open-Laboratory führten zur Erstellung von Anwendungsontologien, die Prozesse und Testmethoden explizit beschreiben. Dabei wurde u.a. der Zugversuch an Metallen bei Raumtemperatur nach DIN EN ISO 6892-1 ontologisch beschrieben. Diese als Beispiel dienende Ontologieentwicklung wird in dieser Präsentation vorgestellt. T2 - Werkstoffprüfung 2021 CY - Online meeting DA - 02.12.2021 KW - Ontologie KW - Semantisches Web KW - Wissensrepräsentation KW - Digitalisierung KW - Zugversuch PY - 2021 AN - OPUS4-53929 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viguier, B. A1 - Epishin, A. A1 - Fedelich, Bernard T1 - Creep of single-crystals of nickel-base gamma-alloy at high temperatures N2 - Porosity in single-crystal nickel-base superalloys is removed by hot isostatic pressing (HIP) at temperatures above gamma’-solvus where the material is very soft and ductile. For example, single-crystal nickel-base superalloy CMSX-4 is HIPed at temperature 1288 °C, which is slightly higher than the gamma’-solvus temperature of this alloy equal to about 1280 °C. It is assumed that pore shrinking during HIP is mostly due to dislocation creep. Such a modelling of HIP of CMSX-4 was started in our group on the base of results of creep tests of [001] single-crystals at 1288 °C [1]. However, it was found later [2] that the alloy CMSX-4 shows very strong creep anisotropy at 1288 °C. Therefore, for calibration of the creep law, creep tests of different orientations under different stress levels are required at the HIP temperature. This was the main task of present work. Single-crystals of CMSX-4 of axial orientations [001], [011], [123] and [111] were cast by VIAM Moscow and tested by BAM Berlin under creep conditions at 1288 °C and stress levels between 4 MPa and 16 MPa. At all stress levels, the creep rate increases by an order of magnitude when changing the orientation from [001] to [111] with [011] and [123] orientations in between. Such a character of creep anisotropy corresponds to the orientation dependence of the Schmid factor for octahedral glide. The crystal viscoplasticity model developed in [1] was improved to better represent the time induced softening observed during creep. The creep tests for different stresses and orientations as well as pore closure were simulated. The results of pore closure simulation are compared with measurements of porosity decrease during Hiping. T2 - 15th International Conference on Creep and Fracture of Engineering Materials and Structures CY - Online meeting DA - 14.06.2021 KW - Nickel-base superalloys KW - Creep KW - Single-Crystal PY - 2021 AN - OPUS4-53935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit A1 - Olbricht, Jürgen A1 - Schilling, Markus A1 - Chen, Yue A1 - Füting, M. A1 - Todor, A. A1 - von Hartrott, P. A1 - Hanke, T. T1 - Wie digitalisieren wir die Werkstoffprüfung? Entwicklung standardisierter Versuchsbeschreibungen und Daten-Infrastrukturen in aktuellen Digitalisierungs-Initiativen N2 - Die Entwicklung digitaler Prozesse für die Materialwissenschaft und Werkstofftechnik muss naturgemäß auch die Charakterisierungsmethoden der Werkstoffprüfung abbilden, die oft durch eine hohe Komplexität gekennzeichnet sind. Als vorteilhaft erweist sich dabei der hohe Standardisierungsgrad, der sich z.B. in klaren Anforderungen an die eingesetzten Prüfmittel und festgelegten Vorgehensweisen ausdrückt. Diese können (und müssen) in entsprechenden digitalen Versuchsbeschreibungen abgebildet werden, wobei sich die klaren Datenstrukturen und Terminologien als vorteilhaft erweisen. T2 - Tagung Werkstoffprüfung 2021: Werkstoffe und Bauteile auf dem Prüfstand Prüftechnik – Kennwertermittlung – Schadensvermeidung CY - Online meeting DA - 02.12.2021 KW - Digitalisierung KW - Standardisierung KW - Normung KW - Ontologien KW - Wissensrepräsentation PY - 2021 AN - OPUS4-53943 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Evans, Alexander A1 - Ávila, Luis A1 - Werner, Tiago A1 - Sommer, Konstantin A1 - Ulbricht, Alexander A1 - Sprengel, Maximilian A1 - Charmi, Amir A1 - Mohr, Gunther A1 - Rehmer, Birgit A1 - Skrotzki, Birgit A1 - Falkenberg, Rainer A1 - Bettge, Dirk A1 - Madia, Mauro A1 - Zerbst, Uwe A1 - Kromm, Arne A1 - Hilgenberg, Kai A1 - Kannengießer, Thomas A1 - Bruno, Giovanni T1 - Ageing behaviour of laser powder bed fused 316L: a powder to failure approach N2 - Laser powder bed fusion (LPBF) is an additive manufacturing process for materials which inherently tends to yield various degrees of metastable hierarchical microstructures, defects and high residual stresses in the as-built condition depending on the process parameters. The understanding of the evolution of these typical features during heat treatment and subsequent thermal and mechanical ageing is crucial for the wider acceptance for safety critical structures. A multi-disciplinary research project at BAM studying the development of the microstructure, defects, residual stresses typical of LPBF 316L and their evolution during thermal and mechanical ageing has led to insights into the stability of these inherent features. This presentation aims to give a broad overview of the project with a few specific cases of investigation. Firstly, the formation of residual stresses, the nature of the initial microstructure, the tensile properties and a modelling approach to understand the anisotropy will be presented. This will be followed by examples of studies of their evolution during heat treatment, long term thermal exposure, and room temperature and high temperature mechanical testing compared to a baseline of conventional wrought variant of the same alloy. T2 - International Conference on Additive Manufacturing 2021 (ICAM 2021) CY - Online meeting DA - 01.11.2021 KW - Ageing KW - Additive manufacturing KW - Laser powder bed fusion KW - AGIL PY - 2021 AN - OPUS4-54106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ta, N. A1 - Bilal, M. U. A1 - Häusler, I. A1 - Saxena, A. A1 - Lin, Y.-Y. A1 - Schleifer, F. A1 - Fleck, M. A1 - Glatzel, U. A1 - Skrotzki, Birgit A1 - Darvishi Kamachali, Reza T1 - Simulation of the θ′ Precipitation Process with Interfacial Anisotropy Effects in Al-Cu Alloys N2 - The effects of anisotropic interfacial properties and heterogeneous elasticity on the growth and ripening of plate-like θ′-phase (Al2Cu) in Al-1.69 at.% Cu alloy are studied. Multi-phase-field simulations are conducted and discussed in comparison with aging experiments. The precipitate/matrix interface is considered to be anisotropic in terms of its energy and mobility. We find that the additional incorporation of an anisotropic interfacial mobility in conjunction with the elastic anisotropy result in substantially larger aspect ratios of the precipitates closer to the experimental observations. The anisotropy of the interfacial energy shows comparably small effect on the precipitate’s aspect ratio but changes the interface’s shape at the rim. The effect of the chemo-mechanical coupling, i.e., the composition dependence of the elastic constants, is studied as well. We show that the inverse ripening phenomenon, recently evidenced for δ’ precipitates in Al-Li alloys (Park et al. Sci. Rep. 2019, 9, 3981), does not establish for the θ′ precipitates. This is because of the anisotropic stress fields built around the θ′ precipitates, stemming from the precipitate’s shape and the interaction among different variants of the θ′ precipitate, that disturb the chemo-mechanical effects. These results show that the chemo-mechanical effects on the precipitation ripening strongly depend on the degree of sphericity and elastic isotropy of the precipitate and matrix phases. KW - Aging KW - Phase-field simulation KW - Interfacial anisotropy KW - Chemo-mechanical coupling KW - Precipitation KW - Elasticity KW - θ′-(Al2Cu) precipitate phase PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522672 DO - https://doi.org/10.3390/ma14051280 VL - 14 IS - 5 SP - 1280 PB - MDPI AN - OPUS4-52267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lin, Y.-Y. A1 - Schleifer, F. A1 - Holzinger, M. A1 - Ta, N. A1 - Skrotzki, Birgit A1 - Darvishi Kamachali, Reza A1 - Glatzel, U. A1 - Fleck, M. T1 - Quantitative Shape-Classification of Misfitting Precipitates during Cubic to Tetragonal Transformations: Phase-Field Simulations and Experiments N2 - The effectiveness of the mechanism of precipitation strengthening in metallic alloys depends on the shapes of the precipitates. Two different material systems are considered: tetragonal γ′′ precipitates in Ni-based alloys and tetragonal θ′ precipitates in Al-Cu-alloys. The shape formation and evolution of the tetragonally misfitting precipitates was investigated by means of experiments and phase-field simulations. We employed the method of invariant moments for the consistent shape quantification of precipitates obtained from the simulation as well as those obtained from the experiment. Two well-defined shape-quantities are proposed: (i) a generalized measure for the particles aspect ratio and (ii) the normalized λ2, as a measure for shape deviations from an ideal ellipse of the given aspect ratio. Considering the size dependence of the aspect ratio of γ′′ precipitates, we find good agreement between the simulation results and the experiment. Further, the precipitates’ in-plane shape is defined as the central 2D cut through the 3D particle in a plane normal to the tetragonal c-axes of the precipitate. The experimentally observed in-plane shapes of γ′′-precipitates can be quantitatively reproduced by the phase-field model. KW - γ″ phase KW - Phase-field simulation KW - Misfitting precipitate KW - Nickel-base alloy KW - Al-Cu alloy KW - θ′ phase KW - Precipitate shape PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522743 DO - https://doi.org/10.3390/ma14061373 VL - 14 IS - 6 SP - 1373 PB - MDPI AN - OPUS4-52274 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kindrachuk, Vitaliy A1 - Klunker, Andre T1 - Phase field modeling of Hertzian cone cracks under spherica indentation N2 - A phase field model of brittle fracture has been developed to simulate the Hertzian crack induced by penetration of a rigid sphere to an isotropic linear-elastic half-space. The fracture formation is regarded as a diffusive field variable, which is zero for the intact material and unity if there is a crack. Crack growth is assumed to be driven by a strain invariant. The numerical implementation is performed with the finite element method and an implicit time integration scheme. The mechanical equilibrium and the phase field equations are solved in a staggered manner, sequentially updating the displacement field and the phase field variable. Numerical examples demonstrate the capability of the model to reproduce the nucleation and growth of the Hertzian cone crack. KW - Hertzian cracks KW - Phase field model KW - Contact mechanics PY - 2021 DO - https://doi.org/10.1007/s11223-021-00251-9 VL - 52 IS - 6 SP - 967 EP - 974 AN - OPUS4-52276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abel, Andreas A1 - Zapala, P. A1 - Michels, H. A1 - Skrotzki, Birgit T1 - Microstructural evolution of Fe-26Al-4Mo-0.5Ti-1B with varying wall thicknesses N2 - With an increasing demand in more efficient fuel consumption to reduce CO2 emissions, weight reductions in high-temperature materials at affordable costs gain increasing attention. One potential candidate is the intermetallic material class of iron aluminides, combining the advantages in mass savings, high temperature performance and recyclability of resources. The alloy Fe-26Al-4Mo-0.5Ti-1B was selected to study the microstructural features evolving from two casting processes, five wall thicknesses and three final conditions. Conclusions are drawn upon the correlations of processing variables, grain sizes and hardness. T2 - DGM Fachausschuss "Intermetallische Phasen" CY - Online meeting DA - 09.02.2021 KW - Intermetallics KW - Iron aluminides KW - Fe-Al alloys KW - Wall thickness KW - Microstructure PY - 2021 AN - OPUS4-52288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Lei A1 - Darvishi Kamachali, Reza T1 - Density-based grain boundary phase diagrams: Application to Fe-Mn-Cr, Fe-Mn-Ni, Fe-Mn-Co, Fe-Cr-Ni and Fe-Cr-Co alloy systems N2 - Phase diagrams are the roadmaps for designing bulk phases. Similar to bulk, grain boundaries can possess various phases, but their phase diagrams remain largely unknown. Using a recently introduced density-based model, here we devise a strategy for computing multi-component grain boundary phase diagrams based on available bulk (CALPHAD) thermodynamic data. Fe-Mn-Cr, Fe-Mn-Ni, Fe-Mn-Co, Fe-Cr-Ni and Fe-Cr-Co alloy systems, as important ternary bases for several trending steels and high-entropy alloys, are studied. We found that despite its solute segregation enrichment, a grain boundary can have lower solubility limit than its corresponding bulk, promoting an interfacial chemical decomposition upon solute segregation. This is revealed here for the Fe-Mn-base alloy systems. The origins of this counter-intuitive feature are traced back to two effects, i.e., the magnetic ordering effect and the low cohesive energy of Mn solute element. Different aspects of interfacial phase stability and GB co-segregation in ternary alloys are investigated as well. We show that the concentration gradient energy contributions reduce segregation level but increase grain boundary solubility limit, stabilizing the GB against a chemical decomposition. Density-based grain boundary phase diagrams offer guidelines for systematic investigation of interfacial phase changes with applications to microstructure defects engineering. KW - Densty-based Thermodynamics KW - Microstrucrue Design KW - Grain Boundary Phase Diagram PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522207 DO - https://doi.org/10.1016/j.actamat.2021.116668 SN - 1359-6454 VL - 207 SP - 116668 PB - Elsevier Ltd. AN - OPUS4-52220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit A1 - Muth, Thilo A1 - Portella, Pedro Dolabella T1 - Interconnecting data repositories: The Platform MaterialDigital (BMBF) N2 - Presentation of the Platform MaterialDigital. Presentation of the needs and challenges in materials science and engineering. T2 - 3rd EMMC International Workshop - EMMC CY - Online meeting DA - 02.03.2021 KW - Digitization KW - Standardization KW - Ontology PY - 2021 AN - OPUS4-52247 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, A. A1 - Fedelich, Bernard A1 - Finn, Monika A1 - Künecke, Georgia A1 - Rehmer, Birgit A1 - Nolze, Gert A1 - Leistner, C. A1 - Petrushin, N. A1 - Svetlov, I. T1 - Investigation of Elastic Properties of the Single-Crystal Nickel-Base Superalloy CMSX-4 in the Temperature Interval between Room Temperature and 1300 °C N2 - The elastic properties of the single-crystal nickel-base superalloy CMSX-4 used as a blade material in gas turbines were investigated by the sonic resonance method in the temperature interval between room temperature and 1300 °C. Elastic constants at such high temperatures are needed to model the mechanical behavior of blade material during manufacturing (hot isostatic pressing) as well as during technical accidents which may happen in service (overheating). High reliability of the results was achieved using specimens of different crystallographic orientations, exciting various vibration modes as well as precise measurement of the material density and thermal Expansion required for modeling the resonance frequencies by finite element method. Combining the results measured in this work and literature data the elastic constants of the gamma and gamma' phases were predicted. This prediction was supported by measurement of the temperature dependence of the gamma'fraction. All data obtained in this work are given in numerical or analytical forms and can be easily used for different scientific and engineering calculations. KW - Nickel-base superalloys KW - Single-crystals KW - Characterization KW - Elastic constants PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520972 DO - https://doi.org/10.3390/cryst11020152 VL - 11 IS - 2 SP - 152 PB - MDPI AN - OPUS4-52097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rockenhäuser, Christian A1 - Rowolt, C. A1 - Milkereit, B. A1 - Darvishi Kamachali, Reza A1 - Kessler, O. A1 - Skrotzki, Birgit T1 - On the long-term aging of S-phase in aluminum alloy 2618A N2 - The aluminum alloy 2618A is applied for engine components such as radial compressor wheels which operate for long time at elevated temperatures. This results in coarsening of the hardening precipitates and degradation in mechanical properties during the long-term operation, which is not taken into account in the current lifetime prediction models due to the lack of quantitative microstructural and mechanical data. To address this issue, a quantitative investigation on the evolution of precipitates during long-term aging at 190 °C for up to 25,000 h was conducted. Detailed transmission electron microscopy (TEM) was combined with Brinell hardness measurements and thorough differential scanning calorimetry (DSC) experiments. The results showthat GPB zones and S-phase Al2CuMg grow up to < 1,000 h during which the GPB zones dissolve and S-phase precipitates form. For longer aging times, only S-phase precipitates coarsen, which can be well described using the Lifshitz–Slyozov Wagner theory of ripening. A thorough understanding of the underlying microstructural processes is a prerequisite to enable the integration of aging behavior into the established lifetime models for components manufactured from alloy 2618A. KW - Long-term aging KW - Transmission electron microscopy (TEM) KW - Differential scanning calorimetry (DSC) KW - Microstructure KW - S-phase KW - Ostwald ripening PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519899 DO - https://doi.org/10.1007/s10853-020-05740-x SN - 0022-2461 VL - 56 IS - 14 SP - 8704 EP - 8716 PB - Springer Nature AN - OPUS4-51989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dub, S. A1 - Haftaoglu, Cetin A1 - Kindrachuk, Vitaliy T1 - Estimate of theoretical shear strength of C60 single crystal by nanoindentation N2 - The onset of plasticity in a single crystal C60 fullerite was investigated by nanoindentation on the (111) crystallographic plane. The transition from elastic to plastic deformation in a contact was observed as pop-in events on loading curves. The respective resolved shear stresses were computed for the octahedral slip systems ⟨011¯¯¯⟩{111}, supposing that their activation resulted in the onset of plasticity. A finite element analysis was applied, which reproduced the elastic loading until the first pop-in, using a realistic geometry of the Berkovich indenter blunt tip. The obtained estimate of the C60 theoretical shear strength was about 1/11 of the shear modulus on {111} planes. KW - Finite element analysis KW - Fullerite KW - Nanoindentation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523208 DO - https://doi.org/10.1007/s10853-021-05991-2 VL - 56 IS - 18 SP - 10905 EP - 10914 PB - Springer Nature AN - OPUS4-52320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit T1 - Verknüpfung von Datenrepositorien: Die Plattform MaterialDigital (PMD) N2 - Vorstellung der Plattform MaterialDigital. Darstellung der Bedürfnisse und Herausforderungen in der Materialwissenschaft und Werkstofftechnik. T2 - Vision Keramik CY - Dresden, Germany DA - 07.06.2022 KW - Digitalisierung KW - Ontologie KW - Standardisierung PY - 2022 AN - OPUS4-54979 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Fedelich, Bernard ED - Cailletaud, G. ED - Cormier, J. ED - Eggeler, G. ED - Maurel, V. ED - Nazé, L. T1 - Crystal orientation and elastic properties N2 - The elastic constants are the most basic mechanical properties of a material and are needed for any structural analysis of a component. For example, they have a major influence on the eigenfrequencies of vibrating parts. Single crystals of Ni-base superalloys are strongly anisotropic, which means that the observed properties are orientation dependent. Tensor algebra is then required to mathematically formulate the elastic properties and their relations to the crystal orientation. Hence, this chapter first summarizes some basic definitions and calculation rules for Rotation matrices, including the definition of the Euler angles, which are most commonly used to define the relative orientations of the crystal and the component. Parts of this chapter closely follow the lines of the excellent exposition of the topic by Olschewski. KW - Nickel-base superalloys KW - Elasticity PY - 2022 SN - 978-0-12-819357-0 SP - 41 EP - 67 PB - Elsevier Inc. AN - OPUS4-53435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Fedelich, Bernard ED - Cailletaud, G. ED - Cormier, J. ED - Eggeler, G. ED - Maurel, V. ED - Nazé, L. T1 - Crystal plasticity models: dislocation based N2 - The large number of TEM investigations and the regular microstructure of single-crystal nickel-base superalloys has boosted the development of a number of physically motivated constitutive laws. In contrast to the more phenomenological models discussed in the next chapter, these models use dislocation densities as internal variables. Obvious advantages are that the computed densities can be compared to TEM observations and the Deformation mechanisms can be easier translated into mathematical equations. KW - Nickel-base superalloys KW - Creep KW - Plasticity PY - 2022 SN - 978-0-12-819357-0 SP - 401 EP - 427 PB - Elsevier Inc. ET - 1 AN - OPUS4-53436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darvishi Kamachali, Reza A1 - Wang, L. T1 - Elastic energy of multi-component solid solutions and strain origins of phase stability in high-entropy alloys N2 - The elastic energy of mixing for multi-component solid solutions is derived by generalizing Eshelby's sphere-in-hole model. By surveying the dependence of the elastic energy on the chemical composition and lattice misfit, we derive a lattice strain coefficient λ*. Studying several high-entropy alloys and superalloys, we propose that most solid solution multi-component alloys are stable when λ*<0.16, generalizing the Hume-Rothery atomic-size rule for binary alloys. We also reveal that the polydispersity index δ, frequently used for describing strain in multi-component alloys, directly represents the elastic energy e with e=qδ², q being an elastic constant. Furthermore, the effects of (i) the number and (ii) the atomic-size distribution of constituting elements on the phase stability of high-entropy alloys were quantified. The present derivations and discussions open for richer considerations of elastic effects in high-entropy alloys, offering immediate support for quantitative assessments of their thermodynamic properties and studying related strengthening mechanisms. KW - Ordering KW - High-entropy alloys KW - Alloy design KW - Strain energy KW - Phase stability PY - 2022 DO - https://doi.org/10.1016/j.scriptamat.2021.114226 SN - 1359-6462 VL - 206 SP - 1 EP - 6 PB - Elsevier CY - Amsterdam AN - OPUS4-53427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gesell, Stephan A1 - Fedelich, Bernard A1 - Ganesh, Rahul A1 - Kuna, Meinhard A1 - Skrotzki, Birgit A1 - Kiefer, Björn T1 - A CTOD-based crack growth law for thermomechanical fatigue N2 - Due to combined cyclic mechanical and thermal loading during operation, the material of exhaust gas conducting components of combustion engines is exposed to thermomechanical fatigue (TMF). This leads to formation and growth of cracks, especially at the most highly stressed points of these components. In order to better predict the service life of cracked components before failure, it is necessary to identify a crack propagation law for the material used. Isothermal crack propagation tests have been carried out at several temperatures with a typical cast iron to identify such a law. The crack length is measured by the potential drop method. The compliance method, fractography and thermographic camera measurements have been used to validate and calibrate the potential drop measurements. Each of the isothermal tests has been simulated using a specially developed FEM-algorithm based on remeshing and remapping. This algorithm has been implemented in python and ABAQUS. Thereby, the crack tip region is modeled by collapsed Quad8 elements. From the individual simulations, the cyclic crack tip opening displacement (ΔCTOD) is extracted and regarded as a potential fracture mechanics parameter which controls the crack growth rate. By combining the data from the experiments and the simulations, the crack propagation law has been identified. Finally, anisothermal crack propagation tests have been performed for validation of the crack growth law. T2 - European Conference on Fracture 2022 CY - Funchal, Portugal DA - 27.06.2022 KW - Fatigue crack growth KW - Finite elmenet simulation KW - TMF experiments PY - 2022 AN - OPUS4-56934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schilling, Markus A1 - Skrotzki, Birgit T1 - Full dataset of several mechanical tests on an S355 steel sheet as reference data for digital representations N2 - The dataset provided in this repository comprises data obtained from a series of characterization tests performed to a sheet of typical S355 (material number: 1.0577) structural steel (designation of steel according to DIN EN 10025-2:2019). The tests include methods for the determination of mechanical properties such as, e.g., tensile test, Charpy test and sonic resonance test. This dataset is intended to be extended by the inclusion of data obtained from further test methods. Therefore, the entire dataset (concept DOI) comprises several parts (versions), each of which is addressed by a unique version DOI. The data were generated in the frame of the digitization project Innovationplatform MaterialDigital (PMD) which, amongst other activities, aims to store data in a semantically and machine understandable way. Therefore, data structuring and data formats are focused in addition to aspects in the field of material science and engineering (MSE). Hence, this data is supposed to provide reference data as basis for experimental data inclusion, conversion and structuring (data management and processing) that leads to semantical expressivity as well as for MSE experts being generally interested in the material properties and knowledge. KW - S355 steel sheet KW - Mechanical testing KW - Tensile test KW - Charpy test KW - Microstructure analysis KW - Digital representation KW - Data management KW - Data format PY - 2022 DO - https://doi.org/10.5281/zenodo.6778336 PB - Zenodo CY - Geneva AN - OPUS4-55141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Han, Ying A1 - Kruse, Julius A1 - Madia, Mauro A1 - Radners, Jan A1 - von Hartrott, Philipp A1 - Skrotzki, Birgit T1 - The influence of aging and mean stress on fatigue of Al-alloy EN AW-2618A N2 - In this study, the influence of aging and mean stress on fatigue of the aluminium-alloy EN AW-2618A is investigated. Therefore axial fatigue tests are carried out on smooth specimens. The experiments show that the fatigue life decreases with increasing mean stress. Furthermore, the tests with the overaged specimens demonstrate that the number of cycles to failure is decreasing with increasing aging time. T2 - LCF9 CY - Berlin, Germany DA - 21.06.2022 KW - Fatigue KW - Aluminium alloy KW - EN AW-2618A KW - Damage Behavior PY - 2022 AN - OPUS4-55125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sonntag, Nadja A1 - Jürgens, Maria A1 - Roohbakhshan, Farshad A1 - Agudo Jácome, Leonardo A1 - Olbricht, Jürgen T1 - Dwell-Fatigue and Cyclic Softening of Grade P92 Steel under LCF and TMF Conditions N2 - Tempered martensite-ferritic steels, such as the grade P92 steel studied in this contribution, exhibit pronounced macroscopic cyclic softening under isothermal low-cycle fatigue (LCF) and non-isothermal thermomechanical fatigue (TMF) conditions, which is considered to be the predominant degradation mechanism in high-temperature fatigue in this and other material groups. However, such softening processes are highly complex since microscopic (e.g., recovery) and macroscopic (e.g., crack initiation and growth), as well as global and local effects superimpose, especially under creep-fatigue conditions. In this contribution, we discuss the cyclic deformation and softening behavior of P92 in strain-controlled LCF, in-phase (IP) TMF, and out-of-phase (OP) TMF tests with and without dwell times in the temperature range from 300 °C to 620°C. EBSD-based dislocation analysis on various fatigued material states confirms the continuous redistribution and annihilation of geometrically necessary dislocations in all studied states, which can be quantitatively correlated with macroscopic softening despite different damage mechanisms for different test types. Deviations from this correlation are observed for OP TMF and LCF with dwell times, i.e., for conditions where optical microscopy reveals pronounced crack-oxidation interactions at the specimen surfaces. T2 - LCF9 - Ninth International Conference on Low Cycle Fatigue CY - Berlin, Germany DA - 21.06.2022 KW - LCF KW - TMF KW - EBSD PY - 2022 DO - https://doi.org/10.48447/LCF9-2022-111 AN - OPUS4-55128 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Skrotzki, Birgit T1 - Brinell-Hardness (HBW 2.5/62.5) of Al-alloy EN AW-2618A after different aging times and temperatures N2 - The dataset contains data from Brinell hardness measurements of Al-alloy EN AW-2618A after aging for different times and temperatures. Aging was either load free or with applied tensile load (creep). KW - Aluminium alloy KW - EN AW-2618A KW - Brinell hardness KW - Aging KW - Creep PY - 2022 UR - https://doi.org/10.5281/zenodo.6787085 UR - https://doi.org/10.5281/zenodo.10396823 DO - https://doi.org/10.5281/zenodo.6787084 PB - Zenodo CY - Geneva AN - OPUS4-55158 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit A1 - von Hartrott, P. T1 - Interlinking Structured Data about Aging and Fattigue of an Aluminum Alloy N2 - In typical material oriented research projects numerous types and sources of data need to get connected to form the final outcome. The data-structures have to be described in a manner semantically concise enough so that all participants share the meaning and at the same time flexible enough to allow connecting findings and facts that have not been connected before. The present contribution describes the approach that is being taken in a public funded research project with two cooperating research institutes. The aim of the data-management solution is to describe and interlink three main entity types: material entities like a test specimen that is under observation, immaterial entities like a fatigue life model and processes that generate and transform the immaterial and material entities. The shared understanding of what is described by the data is achieved by referring to existing linked data resources. In addition a common thesaurus that is subject to ongoing discussion is used for concepts and terms that need precision beyond publicly available concept descriptions. The data associated with the entities and processes and entities is rather small and well structured. The entities and processes covered by the vocabularies are typical to laboratories performing fatigue testing and microstructure analysis. Through the interlinking of the entities and processes it becomes possible to intuitively understand the knowledge that is accumulating in the database. For example it is easy to trace the history of a creep test specimen starting from the chemical composition that has been analyzed for the heat, continuing with the heat treatment of the material, going into the creep test itself with the associated creep data and finally finding the transmission electron microscopy images that have been taken from the crept sample. The presented approach is prototypical way to tackle the sustainable management of structured open research data. Open questions remain for example with the management of attributions, the acceptance of an increased effort in data creation and the access control to specific regions of the data. On the other hand the approach sketches what added value can be created, if the community adopts and contributes to the linked data principles. T2 - LCF9 CY - Berlin, Germany DA - 21.6.2022 KW - Data management KW - Data linking KW - Thesaurus PY - 2022 AN - OPUS4-55159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ávila Calderón, Luis Alexander A1 - Rehmer, Birgit A1 - Graf, B. A1 - Ulbricht, Alexander A1 - Skrotzki, Birgit A1 - Rethmeier, Michael T1 - Low cycle fatigue behavior of DED-L Ti-6AL-4V N2 - Laser powder-based directed energy deposition (DED-L) is a technology that offers the possibility for 3D material deposition over hundreds of layers and has thus the potential for application in additive manufacturing (AM). However, to achieve broad industrial application as AM technology, more data and knowledge about the fabricated materials regarding the achieved properties and their relationship to the manufacturing process and the resulting microstructure is still needed. In this work, we present data regarding the low-cycle fatigue (LCF) behavior of Ti-6Al-4V. The material was fabricated using an optimized DED-L process. It features a low defect population and excellent tensile properties. To assess its LCF behavior two conventionally manufactured variants of the same alloy featuring different microstructures were additionally tested. The strain-controlled LCF tests were carried out in fully reversed mode with 0.3 % to 1.0 % axial strain amplitude from room temperature up to 400°C. The LCF behavior and failure mechanisms are described. For characterization, optical microscopy (OM), scanning electron microscopy (SEM), and micro-computed tomography (µCT) were used. The low defect population allows for a better understanding of the intrinsic material’s properties and enables a fairer comparison against the conventional variants. The fatigue lifetimes of the DED-L material are nearly independent of the test temperature. At elevated test temperatures, they are similar or higher than the lifetimes of the conventional counterparts. At room temperature, they are only surpassed by the lifetimes of one of them. The principal failure mechanism involves multiple crack initiation sites. T2 - Ninth International Conference on Low Cycle Fatigue (LCF9) CY - Berlin, Germany DA - 21.06.2022 KW - AGIL KW - Additive Manufacturing KW - Ti-6Al-4V KW - Low-Cycle-Fatigue KW - Microstructure PY - 2022 AN - OPUS4-55123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Skrotzki, Birgit T1 - Radii of S-phase Al2CuMg in Al-alloy EN AW 2618A after different aging times at 190°C N2 - The dataset contains data from quantitative microstructural analysis of transmission electron microscopy (TEM) studies of the S-phase (Al2CuMg) radii in Al-alloy EN AW 2618A. The investigated material and the applied methods were described in detail in two publications. KW - Aluminium alloy KW - EN AW 2618A a KW - S-phase KW - Al2CuMg KW - Aging KW - Creep KW - Radii distribution KW - TEM PY - 2022 UR - https://doi.org/10.5281/zenodo.6659461 UR - https://doi.org/10.5281/zenodo.7625259 DO - https://doi.org/10.5281/zenodo.6659460 PB - Zenodo CY - Geneva AN - OPUS4-55067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fedelich, Bernard A1 - Butz, Adam A1 - Rehmer, Birgit A1 - Mäde, Lucas A1 - Vöse, Markus T1 - Experimental and analytical investigation of Low Cycle Fatigue Damage at notches in a polycrystalline Nickel base superalloy N2 - Turbine blades often contain cylindric holes used to generate an air film that protects the blade alloy from the hot gases. These cooling holes of diameter around one mm are drilled by laser through the thickness of the blades. Unfortunately, the resulting stress concentration and the drilling-induced damage are known to favor crack initiation from the holes. It is thus necessary to assess the impact of these cooling holes on the structural integrity of the blades. Since cracks initiate very readily, the fatigue life of the components is mainly controlled by the propagation of the cracks in the stress gradient induced by the holes. For this purpose, displacement controlled high-temperature LCF (Low-Cycle-Fatigue) tests were performed with center hole specimens of a coarse-grained Nickel base Superalloy. The tests were stopped after a defined load drop. In addition, crack propagation tests with Double Edge Notch specimens were performed. Moreover, specimens with different hole surface finishes were investigated, which showed a detrimental effect of the hole surface roughness. In parallel, an evaluation of the LCF tests based on a fracture mechanics-based model (Madia et al., Eng. Fract. Mech., 2018) has been applied. Thereby, the specimen life is controlled by the crack propagation time until failure. Crack growth is controlled by a modified NASGRO equation accounting for large-scale yielding and a progressive build-up of crack closure. The initial crack size has been derived from the measurements of defects around the borehole. A reasonable agreement between predicted and measured lifetimes is observed if one keeps in mind the large uncertainty regarding the effective shape of the cracks. T2 - 23rd European Conference on Fracture CY - Funchal, Madeira, Portugal DA - 27.06.2022 KW - Nickel-base superalloys KW - Notches KW - LCF PY - 2022 AN - OPUS4-55338 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhadeliya, Ashok A1 - Rehmer, Birgit A1 - Fedelich, Bernard A1 - Olbricht, Jürgen A1 - Skrotzki, Birgit A1 - Jokisch, T. ED - Zimmermann, M. T1 - Rissfortschrittsuntersuchungen an gefügten Nickelbasiswerkstoffen bei hoher Temperatur N2 - In nickelbasierten Superlegierungen, die für Gasturbinenschaufeln verwendet werden, sind bei hohen Betriebstemperaturen und -belastungen Kriechschäden, Ermüdung, Korrosion und Oxi-dation zu beobachten. Die betroffenen Turbinenschaufeln müssen ersetzt oder repariert werden, um Effizienzverluste und ein eventuelles Bauteilversagen zu vermeiden. In letzter Zeit wurden additive Fertigungs- und Lötverfahren für die Reparatur und das Fügen von Nickelbasiswerk-stoffen entwickelt, um die Einschränkungen der traditionellen Reparaturverfahren zu überwinden. Für eine auslegungsrelevante Bewertung des Risswachstumsverhaltens in den Fügezonen, die durch diese neuen Technologien erzeugt werden, sind Rissfortschrittsuntersuchungen erfor-derlich. Entsprechende Untersuchungen an gefügten Proben werden in diesem Beitrag vorge-stellt. Die Rissfortschrittsversuche werden an gefügten SEN-Proben (Single Edge Notch) bei einem Spannungsverhältnis von 0,1 und einer Temperatur von 950 °C durchgeführt. Das Riss-wachstum wird mit der DCPD-Methode (Direct Current Potential Drop) überwacht, und die ge-messenen Potenzialsignale werden anhand der optisch vermessenen Risslänge und einer Finite-Elemente-Analyse kalibriert. Der Spannungsintensitätsfaktor (SIF) für die gefügte SEN-Geometrie wird mit Hilfe von Finite-Elemente-Analysen berechnet. Auf diese Weise können Rissfortschrittskurven aus den experimentellen Daten abgeleitet werden. T2 - Tagung „Werkstoffprüfung 2022“ CY - Dresden, Germany DA - 27.10.2022 KW - Lötverbindung KW - Rissfortschritt KW - SEN-Probe KW - Gefügte Nickelbasislegierungen PY - 2022 SN - 978-3-88355-430-3 VL - 2022 SP - 67 EP - 72 AN - OPUS4-57090 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shakeel, Yusra A1 - Ávila Calderón, Luis Alexander A1 - Abdildina, Gulzaure A1 - Aversa, Rossella A1 - Blumenröhr, Nicolas A1 - Engstler, Michael A1 - Fell, Jonas A1 - Fritzen, Felix A1 - Hartmann, Volker A1 - Herrmann, Hans-Georg A1 - Jejkal, Thomas A1 - Joseph, Reetu A1 - Kirar, Ajay A1 - Laadhar, Amir A1 - Olbricht, Jürgen A1 - Ost, Philipp A1 - Pauly, Cristoph A1 - Pfeil, Andreas A1 - Roland, Michael A1 - Skrotzki, Birgit A1 - Soysal, Mehmet A1 - Stotzka, Rainer A1 - Vitali, Elias T1 - Creating Exemplary RDM Reference Datasets: Technical Process Overview N2 - The aim of the task area Materials Data Infrastructure (TA-MDI) of the consortium Materials Science and Engineering (MatWerk) of National Research Data Infrastructure (NFDI) is to shape scientific datasets obtained through the Participant Projects (PPs) from a data management perspective conforming to the FAIR principles, making use of the FAIR Digital Object (FAIR DO) concept, including structured metadata and storage solutions. As an example, they apply PP18 (BAM) as a use case to demonstrate the proposed technical workflow. T2 - All-Hands-on-Deck congress from the NFDI-MatWerk CY - Siegburg, Germany DA - 08.03.2023 KW - NFDI KW - Reference Dataset KW - FAIR KW - Research Data Management PY - 2022 AN - OPUS4-57149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beygi Nasrabadi, Hossein A1 - Chen, Yue A1 - Hanke, T. A1 - von Hartrott, P. A1 - Skrotzki, Birgit T1 - Domain-level ontology formulation based on the Platform Material Digital (PMD) ontology: case study Brinell hardness N2 - A large amount of publicly available data is reproduced every day in the field of materials science, while these kind of material data can have different formats and types like paper-type publications, standards, datasheets or isolated datasets in repositories. However, gathering a specific library from such extensive and diverse material data is always challenging for the materials scientists and engineers, since the time-related limitations are not allowed to fully access the large publicly available databases; search across these disparate databases, manage the large volumes of heterogeneous datasets, and integrate data from multiple sources. To address these challenges and make data findable, accessible, interoperable, and reusable (FAIR), an efficient data management system is necessary to build comprehensive, documented, and connected data spaces in the future. A formal standardized knowledge representation through an ontology can address such problems and make data more available and interoperable between related domains. Ontology can also rich machine processable semantic descriptions that increases the performance of scientific searches. In this regard, the Platform MaterialDigital (PMD) is currently working on developing a high-level ontology for the materials and material related processes. For example, in one of the PMD projects of “KupferDigital”, we will try to develop a data ecosystem for digital materials research based on ontology-based digital representations of copper and copper alloys. As a case study, this paper describes the methodology for ontology development of Brinell hardness, based on PMD core ontology. The methodology we describe includes the following steps; gathering the required domain terminology from different resources like standards (DIN EN ISO 6506-1) and test reports, representing the performance of a standard-conformant hardness test and the treatment of the recorded values up to a “reportable” hardness value for a material, designing the process chain according to the semantic technologies, and developing a domain-level ontology of Brinell hardness based on PMD ontology semantic formalization. Apart the mentioned methodology, some interesting tools and methods were introduced and ontology design challenges and possible solutions for modelling materials and processes were discussed. Furthermore, a dataset from the Brinell hardness measurement of cast copper samples is prepared for testing the query process. T2 - MSE 2022 CY - Darmstadt, Germany DA - 27.09.2022 KW - Copper KW - Materials Science KW - Ontology KW - Platform MaterialDigital (PMD) KW - Brinell hardness PY - 2022 AN - OPUS4-56092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus A1 - Bayerlein, Bernd A1 - Marschall, Niklas A1 - von Hartrott, P. A1 - Waitelonis, J. A1 - Hadzic, N. A1 - Birkholz, H. A1 - Grundmann, J. A1 - Chen, Yue A1 - Portella, Pedro Dolabella A1 - Skrotzki, Birgit T1 - Zugversuchsdaten FAIR integriert: Von der normenkonformen Ontologie bis zu interoperablen Daten im Triple Store N2 - Mit der Digitalisierung von Materialien und Prozessen ist ein Paradigmenwechsel in der Materialentwicklung, -gestaltung und -optimierung verbunden, welcher gleichermaßen vielseitige Möglichkeiten eröffnet und eine große Herausforderung darstellt. Insbesondere sind bei den Digitalisierungsbestrebungen die Qualitätssicherung von Prozessen und Ausgabedaten sowie die Interoperabilität zwischen Anwendungen nach FAIR-Prinzipien (Findability, Accessibility, Interoperability, Reusability) sicherzustellen. Dies umfasst die Speicherung, Verarbeitung und Abfrage von Daten in möglichst standardisierter Form, wobei entsprechend auch Normungs- und Standardisierungsgremien beteiligt werden müssen. Um der Herausforderung gerecht zu werden, Materialdaten für alle Beteiligten konsistent zu kontextualisieren, müssen alle notwendigen Informationen zum Zustand des Materials inklusive produktions- und anwendungsbedingter Veränderungen über eine einheitliche, maschinenlesbare Beschreibung verfügbar gemacht werden. Hierfür sollen Ontologien genutzt werden, da sie maschinenverständliche und -interpretierbare Wissensrepräsentationen durch semantische Konzeptualisierungen ermöglichen, die für das Datenmanagement und die Digitalisierung im Bereich der Materialwissenschaften benötigt werden. Dieses hochaktuelle Thema der Integration und Wiederverwendung von Wissen und Daten aus Herstellung, Bearbeitung und Charakterisierung von Materialien wird in den Projekten Innovationsplattform MaterialDigital (PMD, materialdigital.de) und Materials-open-Lab (Mat-o-Lab, matolab.org) adressiert. Diese beiden unter der Beteiligung der Bundeanstalt für Materialforschung und -prüfung (BAM) durchgeführten Projekte wurden auf der 39. Vortrags- und Diskussionstagung „Werkstoffprüfung“ (2021) grundlegend vorgestellt. In dieser Präsentation sollen die Weiterentwicklungen hinsichtlich der Speicherung von Zugversuchsdaten gemäß einer normenkonformen ontologischen Repräsentation vorgestellt werden. Das umfasst den Weg von der Entwicklung einer Ontologie nach Norm, der Konvertierung von Daten aus Standardtests in das interoperable RDF-Format bis hin zur Verknüpfung von Ontologie und Daten. Letztendlich können die entsprechenden Daten in einem Triple Store abgelegt und abgefragt werden. Die übliche Standardisierung von mechanischen Prüfverfahren im Bereich der Materialwissenschaft und Werkstofftechnik dient als solide Grundlage für die Ontologieentwicklung. Daher wurde der Zugversuch von Metallen bei Raumtemperatur nach DIN EN ISO Norm 6892-1:2019-11 als einer der ersten Anwendungsfälle in den genannten Projekten ausgewählt. Die Betrachtung und Beschreibung des Zugversuchs beinhaltet sowohl dessen ontologische Darstellung als auch eine exemplarische Datengenerierung. Die semantische Verbindung von Ontologie und Daten führt zu Interoperabilität und einer verbesserten Abfragefähigkeit. T2 - Tagung Werkstoffprüfung 2022 CY - Dresden, Germany DA - 27.10.2022 KW - Ontologie KW - Semantisches Web KW - Wissensrepräsentation KW - Digitalisierung KW - Zugversuch PY - 2022 AN - OPUS4-56130 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Hennecke, M. ED - Skrotzki, Birgit T1 - Hütte Band 1: Mathematisch-naturwissenschaftliche und allgemeine Grundlagen für Ingenieure N2 - Die HÜTTE ist ein Kompendium und Nachschlagewerk für unterschiedliche Aufgabenstellungen. Durch Kombination der Einzeldisziplinen dieses Wissenskreises kann das multidisziplinäre Grundwissen für die verschiedenen Technikbereiche und Ingenieuraufgaben zusammengestellt werden. Die HÜTTE enthält in drei Bänden - orientiert am Stand von Wissenschaft und Technik und den Lehrplänen der Technischen Universitäten und Hochschulen - die Grundlagen des Ingenieurwissens. Band 1 enthält die mathematisch-naturwissenschaftlichen und allgemeinen Grundlagen. KW - Mathematisch-naturwissenschaftliche Grundlagen KW - Allgemeine Grundlagen PY - 2022 SN - 978-3-662-64368-6 DO - https://doi.org/10.1007/978-3-662-64369-3 SN - 2522-8188 SP - 1 EP - 895 PB - Springer Vieweg CY - Berlin ET - 35 AN - OPUS4-56234 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schröder, Jakob A1 - Evans, Alexander A1 - Polatidis, E. A1 - Čapek, J. A1 - Mohr, Gunther A1 - Serrano Munoz, Itziar A1 - Bruno, Giovanni T1 - Understanding the impact of texture on the micromechanical anisotropy of laser powder bed fused Inconel 718 N2 - The manufacturability of metallic alloys using laser-based additive manufacturing methods such as laser powder bed fusion has substantially improved within the last decade. However, local melting and solidification cause hierarchically structured and crystallographically textured microstructures possessing large residual stress. Such microstructures are not only the origin of mechanical anisotropy but also pose metrological challenges for the diffraction-based residual stress determination. Here we demonstrate the influence of the build orientation and the texture on the microstructure and consequently the mechanical anisotropy of as-built Inconel 718. For this purpose, we manufactured specimens with [001]/[011]-, [001]- and [011]/[111]-type textures along their loading direction. In addition to changes in the Young’s moduli, the differences in the crystallographic textures result in variations of the yield and ultimate tensile strengths. With this in mind, we studied the anisotropy on the micromechanical scale by subjecting the specimens to tensile loads along the different texture directions during in situ neutron diffraction experiments. In this context, the response of multiple lattice planes up to a tensile strain of 10% displayed differences in the load partitioning and the residual strain accumulation for the specimen with [011]/[111]-type texture. However, the relative behavior of the specimens possessing an [001]/[011]- and [001]-type texture remained qualitatively similar. The consequences on the metrology of residual stress determination methods are discussed. KW - Laser powder bed fusion KW - Additive manufacturing KW - Electron backscatter diffraction KW - Tensile testing KW - Diffraction PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555840 DO - https://doi.org/10.1007/s10853-022-07499-9 SN - 1573-4803 VL - 2022 IS - 57 SP - 15036 EP - 15058 PB - Springer Science + Business Media B.V. CY - Dordrecht AN - OPUS4-55584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -