TY - JOUR A1 - Beygi Nasrabadi, Hossein A1 - Bauer, Felix A1 - Uhlemann, Patrick A1 - Thärig, Steffen A1 - Rehmer, Birgit A1 - Skrotzki, Birgit T1 - Mechanical testing dataset of cast copper alloys for the purpose of digitalization N2 - This data article presents a set of primary, analyzed, and digitalized mechanical testing datasets for nine copper alloys. The mechanical testing methods including the Brinell and Vickers hardness, tensile, stress relaxation, and low-cycle fatigue (LCF) testing were performed according to the DIN/ISO standards. The obtained primary testing data (84 files) mainly contain the raw measured data along with the testing metadata of the processes, materials, and testing machines. Five secondary datasets were also provided for each testing method by collecting the main meta- and measurement data from the primary data and the outputs of data analyses. These datasets give materials scientists beneficial data for comparative material selection analyses by clarifying the wide range of mechanical properties of copper alloys, including Brinell and Vickers hardness, yield and tensile strengths, elongation, reduction of area, relaxed and residual stresses, and LCF fatigue life. Furthermore, both the primary and secondary datasets were digitalized by the approach introduced in the research article entitled “Toward a digital materials mechanical testing lab” [1]. The resulting open-linked data are the machine-processable semantic descriptions of data and their generation processes and can be easily queried by semantic searches to enable advanced data-driven materials research. KW - FAIR principles KW - Hardness KW - Low-Cycle Fatigue (LCF) KW - Tensile testing KW - Stress relaxation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605005 DO - https://doi.org/10.1016/j.dib.2024.110687 SN - 2352-3409 SP - 1 EP - 15 PB - Elsevier BV AN - OPUS4-60500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Han, Ying A1 - Kruse, Julius A1 - Rosalie, Julian A1 - Radners, J. A1 - von Hartrott, P. A1 - Skrotzki, Birgit T1 - Influence of mean stress and overaging on fatigue life of aluminum alloy EN AW-2618A N2 - Fatigue tests were performed on the forged aluminum alloy EN AW-2618A in the T61 state. Different stress ratios (R = -1, R = 0.1) were selected to study the influence of mean stress on fatigue life. Two overaged states (10 h/230 ◦C, 1000 h/230 ◦C) were also tested to investigate the influence of overaging on fatigue life. Transmission electron microscopy (TEM) was used to characterize the precipitates (S-phase), which are mainly responsible for the strength of the alloy. A fractographic analysis was also performed to determine the failure mode. Overaging reduces the fatigue life compared to the T61 state. The longer the aging time, the lower the fatigue resistance. The reason is the decrease in (yield) strength, which correlates with the radius of the S-phase: the precipitate radius increases by a factor of approximately two for the overaged states compared to the initial state. The analysis of the fracture surfaces showed crack initiation occurs predominantly on the outer surface and is associated with the primary phases. KW - Aluminum alloys KW - Aging KW - Fatigue KW - Microstructure KW - Electron microscopy KW - S-Phase PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583708 DO - https://doi.org/10.1016/j.msea.2023.145660 SN - 0921-5093 VL - 886 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-58370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rehmer, Birgit A1 - Bayram, Faruk A1 - Ávila Calderón, Luis A1 - Mohr, Gunther A1 - Skrotzki, Birgit T1 - Elastic modulus data for additively and conventionally manufactured variants of Ti-6Al-4V, IN718 and AISI 316 L N2 - This article reports temperature-dependent elastic properties (Young’s modulus, shear modulus) of three alloys measured by the dynamic resonance method. The alloys Ti-6Al-4V, Inconel IN718, and AISI 316 L were each investigated in a variant produced by an additive manufacturing processing route and by a conventional manufacturing processing route. The datasets include information on processing routes and parameters, heat treatments, grain size, specimen dimensions, and weight, as well as Young’s and shear modulus along with their measurement uncertainty. The process routes and methods are described in detail. The datasets were generated in an accredited testing lab, audited as BAM reference data, and are hosted in the open data repository Zenodo. Possible data usages include the verification of the correctness of the test setup via Young’s modulus comparison in low-cycle fatigue (LCF) or thermo-mechanical fatigue (TMF) testing campaigns, the design auf VHCF specimens and the use as input data for simulation purposes. KW - Elastic modulus KW - Young's modulus KW - Shear modulus KW - Additive manufacturing KW - AISI 316L KW - IN 718 KW - Ti-6Al-4V KW - Reference data KW - Temperature dependence PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579716 DO - https://doi.org/10.1038/s41597-023-02387-6 VL - 10 IS - 1 SP - 1 EP - 9 PB - Springer Nature AN - OPUS4-57971 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sonntag, Nadja A1 - Jürgens, Maria A1 - Uhlemann, Patrick A1 - Skrotzki, Birgit A1 - Olbricht, Jürgen T1 - Experimental data from service-like creep-fatigue experiments on grade P92 steel N2 - This article refers to the research article entitled “Creep-Fatigue of P92 in Service-Like Tests with Combined Stress- and Strain-Controlled Dwell Times” [1]. It presents experimental mechanical data from complex service-like creep-fatigue experiments performed isothermally at 620 °C and a low strain amplitude of 0.2 % on tempered martensite-ferritic grade P92 steel. The data sets in text file format provide cyclic deformation (min. and max. stresses) and the total (hysteresis) data of all recorded fatigue cycles for three different creep-fatigue experiments: 1) a standard relaxation fatigue (RF) test with symmetrical dwell times of three minutes introduced at minimum and maximum strain, 2) a fully strain-controlled service-like relaxation (SLR) test combining these three-minute peak strain dwells with a 30-minute dwell in between at zero strain, and 3) a partly stress-controlled service-like creep (SLC) test combining the three-minute peak strain dwells with 30-minute dwells at constant stress. Such service-like (SL) tests with additional long-term stress- and strain-controlled dwell times are non-standard, rare, and expensive, making these data very valuable. They may be used to approximate cyclic softening in the technically relevant range, for the design of complex SL experiments, or for detailed analyses of stress-strain hystereses (e.g., for stress or strain partitioning methods, for the determination of hysteresis energies (work), inelastic strain components, etc.). In addition, the latter analyses may supply important input for advanced parametric lifetime modeling of components under creep-fatigue loading or model calibration parameters. KW - Tempered martensite-ferritic steel KW - Creep KW - Stress relaxation KW - Creep-fatigue KW - Dwell times PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-578407 DO - https://doi.org/10.1016/j.dib.2023.109333 SN - 2352-3409 VL - 49 SP - 1 EP - 9 PB - Elsevier Inc. AN - OPUS4-57840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühn, Hans-Joachim A1 - Rehmer, Birgit A1 - Skrotzki, Birgit T1 - Thermomechanical fatigue of heat-resistant austenitic cast iron EN-GJSA-XNiSiCr35-5-2 (Ni-Resist D-5S) N2 - TMF tests were carried out on EN-GJSA-XNiSiCr35-5-2 at constant minimum temperature (400 °C) and varying maximum temperatures (Tmax = 700 °C, 800 °C, 900 °C) with hold times of 180 s at Tmax and two phase angles (in-phase (IP), 180° out-of-phase (OP)). The results showed a comparable strength under OP- and IP-TMF loading. At Tmax = 700 °C and 900 °C, the lifetime in IP-tests was slightly longer than that of OP-tests, while it is vice versa at Tmax = 800 °C. The IP-tests at Tmax = 900 °C showed a similar lifetime as OP-tests at Tmax = 700 °C and 800 °C, which was unexpected for such a high testing temperature. All IP-tests at Tmax = 900 °C showed a continuous cyclic softening from the beginning on, which was different from all other testing conditions. Complementary metallographic investigations indicated that under this test condition, intergranular creep damage is present in the volume of the test pieces. T2 - 3rd International Workshop on Thermo-Mechanical Fatigue (TMF-Workshop 2016) CY - Berlin, Germany DA - 27.04.2016 KW - Cast iron KW - Cracks KW - Cyclic softening KW - Microscopy KW - Thermomechanical fatigue PY - 2017 DO - https://doi.org/10.1016/j.ijfatigue.2017.01.009 SN - 0142-1123 SN - 1879-3452 VL - 99 IS - 2 (Special issue: Recent developments in thermo-mechanical fatigue) SP - 295 EP - 302 PB - Elsevier CY - Oxford AN - OPUS4-39680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jentzsch, Stefan A1 - Stock, Daniel A1 - Häcker, Ralf A1 - Skrotzki, Birgit A1 - Darvishi Kamachali, Reza A1 - Klingbeil, Dietmar A1 - Kindrachuk, Vitaliy T1 - Shear Band Formation with Split Hopkinson Bar Experiments N2 - The essence of dynamic failure is closely linked to dramatic shear deformations which often lead to the formation of adiabatic shear bands (ASB). Under high loading velocities and the subsequent rapid temperature increase, the localization of shear strain is crucial in view of safety issues of systems in mechanical and aircraft engineering, especially with respect to fast rotating components and diverse crash scenarios. In this research, we perform high speed impact tests at the split Hopkinson pressure bar (SHPB) setup and use particular hat-shaped specimen geometries that resemble the stresses and failure conditions at the component level. In the first step, we specify a notched specimen geometry using finite element (FE) simulations to ensure pure shear. Further, quasi-static compressive tests and a series of impact tests at high strain rates of 10^3-10^4 s^-1 are conducted on specimens manufactured from a fine-grain structural steel with the properties of S355. Optical microscopy and electron backscatter diffraction (EBSD) of the sheared zones unveil significant localization to maximal shear strains of about 0.9 accompanied by grain refinement by factors 5 to 14. The displacements across the surface of the specimens are captured with subset-based local digital image correlation (DIC) during the impact time, and serve as an objective to validate a viscoplastic constitutive relationship. More precisely, the deformation distribution is accurately reproduced by the widely recognized Johnson-Cook (JC) model, which features an enhanced description of damage evolution. Thus, combining experimental and characterization techniques, continuum mechanics and reasonable optimization strategies for the identification of model parameters provides an efficient approach for comprehensive insights into the strain localization behaviour and its impact on the mechanical performance of S355 under extreme strain rates and deformations. KW - Adiabatic shear bands KW - Finite element analysis KW - Viscoplastic material modelling KW - Split Hopkinson pressure bar KW - Hat-shaped specimen KW - Johnson–Cook parameter identification PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613339 DO - https://doi.org/10.1016/j.ijmecsci.2024.109749 VL - 284 SP - 1 EP - 14 PB - Elsevier BV AN - OPUS4-61333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eisenbart, Miriam A1 - Hanke, Thomas A1 - Bauer, Felix A1 - Beygi Nasrabadi, Hossein A1 - Junghanns, Kurt A1 - Dziwis, Gordian A1 - Tikana, Ladji A1 - Parvez, Ashak Mahmud A1 - van den Boogaart, Karl Gerald A1 - Sajjad, Mohsin A1 - Friedmann, Valerie A1 - Preußner, Johannes A1 - Ramakrishnan, Anantha Narayanan A1 - Klengel, Sandy A1 - Meyer, Lars‐Peter A1 - Martin, Michael A1 - Klotz, Ulrich Ernst A1 - Skrotzki, Birgit A1 - Weber, Matthias T1 - KupferDigital: Ontology‐Based Digital Representation for the Copper Life Cycle N2 - The copper life cycle comprises numerous stages from the alloy production to the manufacturing and usage of engineered parts until recycling. At each step, valuable data are generated and stored; some are transferred to the subsequent stations. A thorough understanding of the materials’ behavior during manufacturing processes or throughout their product lifetime is highly dependent on a reliable data transfer. If, for example, a failure occurs during the service life, information about the manufacturing route can be of decisive importance for detecting the root cause of the failure. Additionally, the life cycle assessment hinges on the availability of data. Recording and storing interoperable structured data is, therefore, a thriving research field with huge implications for the economic strength of the manufacturing industry. In the KupferDigital project, it is demonstrated how an ontology‐based data space can be utilized not only as an innovative method for storing and providing interoperable life cycle data but also as a means to enable automated data analysis and evaluation, leading to new insights and the creation of new knowledge using semantic data and technologies. This work illustrates how data recorded at different research facilities can be integrated into one single data space, allowing queries across heterogeneous sources. KW - Copper Alloy KW - Ontology KW - Digitalization KW - Data Space KW - Semantic Representation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630213 SN - 1527-2648 DO - https://doi.org/10.1002/adem.202401735 VL - 27 IS - 8 SP - 1 EP - 29 PB - Wiley AN - OPUS4-63021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - 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 - JOUR A1 - Ulbricht, Alexander A1 - Ávila Calderón, Luis A1 - Sommer, Konstantin A1 - Mohr, Gunther A1 - Evans, Alexander A1 - Skrotzki, Birgit A1 - Bruno, Giovanni T1 - Evolution of Creep Damage of 316L Produced by Laser Powder Bed Fusion N2 - The damage mechanisms of metallic components produced by process laser powder bed fusion differ significantly from those typically observed in conventionally manufactured variants of the same alloy. This is due to the unique microstructures of additively manufactured materials. Herein, the focus is on the study of the evolution of creep damage in stainless steel 316L specimens produced by laser powder bed fusion. X-ray computed tomography is used to unravel the influence of the process-specific microstructure from the influence of the initial void distribution on creep damage mechanisms. The void distribution of two specimens tested at 600 °C and 650 °C is analyzed before a creep test, after an interruption, and after fracture. The results indicate that the formation of damage is not connected to the initial void distribution. Instead, damage accumulation at grain boundaries resulting from intergranular cracking is observed. KW - Creep KW - Computed Tomography KW - PBF-LB/M/316L KW - Laser Powder Bed Fusion KW - Microstructure KW - AISI 316L KW - Additive Manufacturing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574127 DO - https://doi.org/10.1002/adem.202201581 SP - 1 EP - 9 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-57412 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 -