TY - JOUR A1 - Schilling, Markus A1 - Bruns, Sebastian A1 - Bayerlein, Bernd A1 - Kryeziu, Jehona A1 - Schaarschmidt, Jörg A1 - Waitelonis, Jörg A1 - Dolabella Portella, Pedro A1 - Durst, Karsten T1 - Seamless Science: Lifting Experimental Mechanical Testing Lab Data to an Interoperable Semantic Representation N2 - The scientific landscape is undergoing rapid transformations with the advent of the digital age which revolutionizes research methodologies. In materials science and engineering, an adoption of modern data management techniques is desirable to maximize the efficiency and accessibility of research efforts. Traditional practices in testing laboratories are usually inadequate for efficient data acquisition and utilization as they lead to local storage and difficulty in publication and correlation with other results. Electronic laboratory notebooks (ELNs) are promising prospects in this respect. Semantic concepts and ontologies enhance interoperability by standardizing experimental data representation. An in‐laboratory pipeline seamlessly integrating an ELN with transformation scripts to convert experimental into interoperable data in a machine‐actionable format is created in this study as a proof of concept. Tensile test results and the corresponding tensile test ontology are used exemplary. Linking ELN data to semantic concepts enriches the stored information while improving interpretability and reusability. Involving undergraduate students builds a bridge between theory and practice during their training and promotes their digital skills. This study underscores the potential of ELNs and knowledge representations as beneficial means toward improved data management practices that enhance collaborative research and education while ensuring compatibility with evolving standards and technologies. KW - Semantic Data KW - Data Integration KW - Tensile Test Ontology KW - Electronic Lab Notebook KW - Wissensrepräsentation KW - Education PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618251 DO - https://doi.org/10.1002/adem.202401527 SP - 1 EP - 13 PB - Wiley VHC-Verlag AN - OPUS4-61825 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Portella, Pedro Dolabella A1 - Helmerich, Rosemarie T1 - Adolf Martens and his contribution to materials engineering N2 - Adolf Martens (1850–1914) was a pioneer of materials engineering. After his studies in Berlin he joined a railway company being responsible for the technical equipment. His interest for the basic mechanisms of mechanical strength and fracture of metallic materials led him to the development of the basic concepts for metallography; his papers published between 1878 and 1889 laid the fundament of this technique. In 1880 Martens changed to the Royal Industrial Academy in Berlin and by 1884 he was designated as director of the Materials Testing Laboratory at the Technical University Berlin. Under his guidance this institution acquired an excellent reputation in all relevant areas of the German industry, forming the nucleus of the Bundesanstalt für Materialforschung und -prüfung (BAM) – the Federal Institute for Materials Research and Testing. Martens developed equipment in many different areas as mechanical testing of metallic materials and of paper, characterization of the wear behavior of materials and viscosity of lubricants. His overwhelming contribution to materials engineering was recognized as early as 1895 by Floris Osmond, who denominated martensite a metallographical constituent resulting from quenching of steels. In 2000 ISO designated the value obtained from the instrumented indentation method as Martens Hardness – HM. KW - Adolf Martens KW - Microscopy KW - Metallography KW - Mechanical testing KW - Quality assurance in materials testing PY - 2014 DO - https://doi.org/10.1016/j.engfailanal.2014.03.001 SN - 1350-6307 SN - 1873-1961 VL - 43 IS - Special Issue 'A Tribute to Prof. A. Martens' SP - 2 EP - 10 PB - Elsevier Science Publ. CY - Oxford AN - OPUS4-30865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, Alexander A1 - Link, T. A1 - Portella, Pedro Dolabella A1 - Brückner, Udo T1 - Evolution of the gamma/gamma'-microstructure during high-temperature creep of a nickel-base superalloy KW - Nickel alloys KW - Creep KW - Mesostructure KW - Scanning electron microscopy (SEM) KW - Image analysis PY - 2000 SN - 1359-6454 SN - 1873-2453 VL - 48 SP - 4169 EP - 4177 PB - Elsevier Science CY - Kidlington AN - OPUS4-7152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, Alexander A1 - Brückner, Udo A1 - Portella, Pedro Dolabella A1 - Link, T. T1 - Influence of small rhenium additions on the lattice spacing of nickel solid solution N2 - The influence of small rhenium additions on the lattice spacing of a nickel solid solution was investigated using a nickel–rhenium single crystal with an axial macrosegregation of rhenium. The effect of rhenium on the lattice spacing of the nickel solid solution was found to be similar to that of tungsten. KW - Nickel alloys KW - Crystallography PY - 2003 DO - https://doi.org/10.1016/S1359-6462(02)00436-0 SN - 1359-6462 SN - 1872-8456 VL - 48 IS - 4 SP - 455 EP - 459 PB - Elsevier CY - Oxford AN - OPUS4-2278 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jiao, Feng A1 - Österle, Werner A1 - Portella, Pedro Dolabella A1 - Ziebs, Josef T1 - Biaxial path-dependence of low-cycle fatigue behaviour and microstructure of alloy 800 H at room temperature N2 - Low-cycle fatigue experiments under combined axial-torsional loading have been carried out on alloy 800 H tubular specimens at room temperature. In comparison with proportional loading, an extra cyclic hardening effect produced by nonproportional loading was observed. The microstructure study highlights the fact that the dislocation arrangement under proportional loading is significantly different from that under nonproportional loading. Mechanical twinning was found in specimens cycled under axial loading and nonproportional loading. It is suggested that mechanical twinning depends not only on shear stress but also on normal stress on the plane of maximum shearing. The extra hardening can be interpreted in terms of the deformation microstructure. Fatigue cracking was initiated generally at the specimen surfaces along the plane of maximum shearing, but under nonproportional loading cracks were found also in the bulk of the specimens. Transcrystalline crack propagation was observed in the specimens after proportional and nonproportional LCF tests. PY - 1995 DO - https://doi.org/10.1016/0921-5093(94)09690-2 SN - 0921-5093 SN - 1873-4936 VL - 196 IS - 1 SP - 19 EP - 24 PB - Elsevier CY - Amsterdam AN - OPUS4-2503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - De Araújo, A. A1 - Panossian, Z. A1 - Portella, Pedro Dolabella A1 - Bäßler, Ralph T1 - Monitoramento da corrosao em estruturas de concreto: sensor galvânico N2 - O monitoramento das estruturas de concreto possibilita que o risco de corrosão seja estimado ao longo dos anos de sua utilização. Com o conhecimento desse risco, intervenções de prevenção da corrosão ou de controle da corrosão já estabelecida podem ser programadas e realizadas em períodos adequados. Na prática, o risco de corrosão é avaliado por meio da verificação periódica do estado da armadura e das alterações nas propriedades do concreto. Isso pode ser feito por meio do embutimento no concreto de cobrimento de sensores de aquisição contínua de dados. Há diferentes tipos de sensores de aquisição contínua de dados. Um dos mais conhecidos é o sensor galvânico que consta de um conjunto de barras de aço-carbono, eletricamente isoladas. Com o embutimento do sensor, essas barras ficam posicionadas em diferentes e conhecidas profundidades do concreto de cobrimento da armadura. O risco de corrosão da armadura é monitorado com a periódica medição da corrente galvânica em cada uma das barras do sensor. Essa medição, dentre outras informações do sensor galvânico foram abordadas em artigo anterior. Além do sensor galvânico, destacam-se o sensor de umidade e o de taxa de corrosão, que monitoram parâmetros importantes relacionados ao estabelecimento e evolução de processo corrosivo das armaduras. A seguir esses sensores são apresentados, bem como o sensor de fibra óptica, o qual apresenta algumas vantagens em relação aos demais mencionados, embora ainda seja de uso restrito. KW - Sensor da corrosao PY - 2013 SN - 0104-1053 VL - 194 IS - Maio SP - 62 EP - 66 PB - PINI AN - OPUS4-29403 LA - por AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kannengießer, Thomas A1 - Rethmeier, Michael A1 - Portella, Pedro Dolabella A1 - Ewert, Uwe A1 - Redmer, Bernhard T1 - Assessment of hot cracking behaviour in welds N2 - Hot crack assessment during production and processing of metallic materials is an essential prerequisite for the safety of welded structures. The hot cracking investigations presented here were carried out as part of a study aimed at the development of Cr/Ni low transformation temperature filler materials. Low transformation temperature alloys open up the possibility for welding high strength steels. The externally loaded Modified Varestraint Transvarestraint hot cracking test was employed in the experiments described. The hot cracking resistance was evaluated with the help of light microscopy applied at the specimen surface. The proportionality between hot cracking susceptibility and Cr/Ni alloy content was explained by the altered solidification kinetics and by the enlarged solidification interval. The internal crack paths and the three-dimensional structure of the crack net in the material volume were examined using X-ray computer tomography. The total crack lengths for different material depths and circumjacent rectangular volumes, respectively, were be determined. An increasing hot cracking susceptibility with increasing Cr/Ni alloy content was also be established for the specimen volume. KW - Hot cracking KW - Low transformation temperature (LTT) alloy KW - Modified varestraint transvarestraint (MVT) hot cracking test KW - X-ray computer tomography PY - 2011 DO - https://doi.org/10.3139/146.110545 SN - 1862-5282 VL - 102 IS - 8 SP - 1001 EP - 1006 PB - Carl Hanser CY - München AN - OPUS4-24400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Andrade Silva, F. A1 - Williams, J. J. A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. A1 - Portella, Pedro Dolabella A1 - Chawla, N. T1 - Three-dimensional microstructure visualization of porosity and Fe-rich inclusions in SiC particle-reinforced Al alloy matrix composites by X-ray synchrotron tomography N2 - Microstructural aspects of composites such as reinforcement particle size, shape, and distribution play important roles in deformation behavior. In addition, Fe-rich inclusions and porosity also influence the behavior of these composites, particularly under fatigue loading. Three-dimensional (3-D) visualization of porosity and Fe-rich inclusions in three dimensions is critical to a thorough understanding of fatigue resistance of metal matrix composites (MMCs), because cracks often initiate at these defects. In this article, we have used X-ray synchrotron tomography to visualize and quantify the morphology and size distribution of pores and Fe-rich inclusions in a SiC particle-reinforced 2080 Al alloy composite. The 3-D data sets were also used to predict and understand the influence of defects on the deformation behavior by 3-D finite element modeling. KW - Synchrotron radiation KW - X-ray tomography KW - X-ray refraction KW - Analyser based imaging KW - Metal matrix composite (MMC) KW - Fatigue PY - 2010 DO - https://doi.org/10.1007/s11661-010-0260-0 SN - 1073-5623 SN - 1543-1940 VL - 41 IS - 8 SP - 2121 EP - 2128 PB - The Minerals, Metals and Materials Society CY - Warrendale AN - OPUS4-21629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayerlein, Bernd A1 - Waitelonis, Jörg A1 - Birkholz, Henk A1 - Jung, Matthias A1 - Schilling, Markus A1 - v. Hartrott, Philipp A1 - Bruns, Marian A1 - Schaarschmidt, Jörg A1 - Beilke, Kristian A1 - Mutz, Marcel A1 - Nebel, Vincent A1 - Königer, Veit A1 - Beran, Lisa A1 - Kraus, Tobias A1 - Vyas, Akhilesh A1 - Vogt, Lars A1 - Blum, Moritz A1 - Ell, Basil A1 - Chen, Ya‐Fan A1 - Waurischk, Tina A1 - Thomas, Akhil A1 - Durmaz, Ali Riza A1 - Ben Hassine, Sahar A1 - Fresemann, Carina A1 - Dziwis, Gordian A1 - Beygi Nasrabadi, Hossein A1 - Hanke, Thomas A1 - Telong, Melissa A1 - Pirskawetz, Stephan A1 - Kamal, Mohamed A1 - Bjarsch, Thomas A1 - Pähler, Ursula A1 - Hofmann, Peter A1 - Leemhuis, Mena A1 - Özçep, Özgür L. A1 - Meyer, Lars‐Peter A1 - Skrotzki, Birgit A1 - Neugebauer, Jörg A1 - Wenzel, Wolfgang A1 - Sack, Harald A1 - Eberl, Chris A1 - Portella, Pedro Dolabella A1 - Hickel, Tilmann A1 - Mädler, Lutz A1 - Gumbsch, Peter T1 - Concepts for a Semantically Accessible Materials Data Space: Overview over Specific Implementations in Materials Science N2 - This article describes advancements in the ongoing digital transformation in materials science and engineering. It is driven by domain‐specific successes and the development of specialized digital data spaces. There is an evident and increasing need for standardization across various subdomains to support science data exchange across entities. The MaterialDigital Initiative, funded by the German Federal Ministry of Education and Research, takes on a key role in this context, fostering collaborative efforts to establish a unified materials data space. The implementation of digital workflows and Semantic Web technologies, such as ontologies and knowledge graphs, facilitates the semantic integration of heterogeneous data and tools at multiple scales. Central to this effort is the prototyping of a knowledge graph that employs application ontologies tailored to specific data domains, thereby enhancing semantic interoperability. The collaborative approach of the Initiative's community provides significant support infrastructure for understanding and implementing standardized data structures, enhancing the efficiency of data‐driven processes in materials development and discovery. Insights and methodologies developed via the MaterialDigital Initiative emphasize the transformative potential of ontology‐based approaches in materials science, paving the way toward simplified integration into a unified, consolidated data space of high value. KW - Semantic Interoperability KW - Data Spaces KW - Integration Workflows KW - MaterialDigital PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622952 DO - https://doi.org/10.1002/adem.202401092 SN - 1527-2648 SP - 1 EP - 25 PB - Wiley-VCH CY - Weinheim AN - OPUS4-62295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fedelich, Bernard A1 - Epishin, A. A1 - Link, T. A1 - Klingelhöffer, Hellmuth A1 - Künecke, Georgia A1 - Portella, Pedro Dolabella T1 - Experimental characterization and mechanical modeling of creep induced rafting in superalloys N2 - A constitutive model has been developed for the high temperature mechanical behavior of single crystal superalloys, including rafting and its consequences. The flow stress depends on the γ channel width via the Orowan stress. An evolution equation for channel widening during high temperature straining has been derived and calibrated with measurements. Therein, rafting is assumed to be driven by the relaxation of internal stresses. The model is able to represent the mechanical softening at high stresses consecutive to rafting. The model has been applied to simulate rafting during uniaxial creep in several crystal orientations, in notched specimens as well as in cyclically loaded specimens. KW - Single crystal KW - Superalloys KW - Rafting KW - Creep KW - Viscoplasticity KW - Constitutive law PY - 2012 DO - https://doi.org/10.1016/j.commatsci.2012.05.071 SN - 0927-0256 VL - 64 SP - 2 EP - 6 PB - Elsevier CY - Amsterdam AN - OPUS4-26401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epishin, Alexander A1 - Link, T. A1 - Klingelhöffer, Hellmuth A1 - Fedelich, Bernard A1 - Portella, Pedro Dolabella T1 - Creep damage of single-crystal nickel base superalloys: mechanisms and effect on low cycle fatigue N2 - The main mechanisms of creep damage of single-crystal nickel-base superalloys are the loss of the interface coherency, coarsening of the γ / γ'-microstructure, precipitation of topologically closed packed phases and growth of porosity. This degradation deteriorates the mechanical properties such as yield stress, creep lifetime and especially low-cycle fatigue life, which can be reduced nearly by a factor of 10. The degradation kinetics during creep was characterised quantitatively on the superalloy CMSX-4. A new non-destructive testing technique was applied to cover a wide test parameter range with few specimens in a relatively short time: repeated load annealing of wedge shaped specimens. KW - Creep damage KW - Nickel-base superalloys KW - Low-cycle fatigue KW - Rafting KW - Porosity KW - Prior exposure PY - 2010 DO - https://doi.org/10.3184/096034009X12603595726283 SN - 0960-3409 VL - 27 IS - 1 SP - 53 EP - 59 PB - Science Reviews CY - St. Albans, Herts. [u.a.] AN - OPUS4-23912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fedelich, Bernard A1 - Künecke, Georgia A1 - Epishin, A. A1 - Link, T. A1 - Portella, Pedro Dolabella T1 - Constitutive modelling of creep degradation due to rafting in single-crystalline Ni-base superalloys N2 - A constitutive model for the mechanical behaviour of single-crystalline superalloys at high temperatures has been developed. The model relies on the slip system theory and is able to predict rafting and its influence on plastic flow. The kinetics of rafting are assumed to be driven by the reduction of the internal stresses represented by the macroscopic back-stress. The rafting effect is incorporated in the model through the dependence of the Orowan stress on the channel width. The model has been validated for the alloy CMSX-4 at 950 °C. The rafting part of the model has been calibrated by measurements of the channel widths after several levels of creep strains and for several loads. KW - Single crystal superalloy KW - Creep KW - Rafting KW - Constitutive modelling KW - Viscoplasticity PY - 2009 DO - https://doi.org/10.1016/j.msea.2008.04.089 SN - 0921-5093 SN - 1873-4936 VL - 510-511 SP - 273 EP - 277 PB - Elsevier CY - Amsterdam AN - OPUS4-19353 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -