TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - VAMAS TWA 37 - Quantitative Microstructural Analysis & Liaison with ISO/TC 202 Microbeam Analysis, Liaison with ISO N2 - The progress in activities on Microbeam Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 is presented and discussed with respect to the possibility of identifying and launching related VAMAS projects. Need of more promotion for the engagement of more participants from industry and academia at national, European and international level is highlighted. Also, the competition with the other technical working areas (on 'nano' or materials-related) is critically discussed. Further, a short overview of the VAMAS areas of activities is given where Germany is involved. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 46th Steering Committee Meeting CY - Online meeting DA - 08.09.2021 KW - VAMAS KW - Nanoparticles KW - Standardisation KW - Inter-laboratory comparison KW - ISO/TC 202 KW - ISO/TC 229 KW - ISO/TC 201 KW - Microstructure KW - EBSD PY - 2021 UR - http://www.vamas.org/twa/ AN - OPUS4-53237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tokarski, T. A1 - Nolze, Gert A1 - Winkelmann, A. A1 - Rychlowski, L. A1 - Bala, P. A1 - Cios, G. T1 - Transmission Kikuchi diffraction: The impact of the signal-to-noise ratio N2 - Signal optimization for transmission Kikuchi diffraction (TKD) measurements in the scanning electron microscope is investigated by a comparison of different sample holder designs. An optimized design is presented, which uses a metal shield to efficiently trap the electron beam after transmission through the sample. For comparison, a second holder configuration allows a significant number of the transmitted electrons to scatter back from the surface of the sample holder onto the diffraction camera screen. It is shown that the secondary interaction with the sample holder leads to a significant increase in the background level, as well as to additional noise in the final Kikuchi diffraction signal. The clean TKD signal of the optimized holder design with reduced background scattering makes it possible to use small signal changes in the range of 2% of the camera full dynamic range. As is shown by an analysis of the power spectrum, the signal-to-noise ratio in the processed Kikuchi diffraction patterns is improved by an order of magnitude. As a result, the optimized design allows an increase in pattern signal to noise ratio which may lead to increase in measurement speed and indexing reliability. KW - EBSD KW - SEM KW - Transmission Kikuchi diffraction KW - Sample holder PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531743 DO - https://doi.org/10.1016/j.ultramic.2021.113372 SN - 0304-3991 SN - 1879-2723 VL - 230 SP - 1 EP - 8 PB - Elsevier CY - Amsterdam AN - OPUS4-53174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sobol, Oded A1 - Holzlechner, Gerald A1 - Nolze, Gert A1 - Wirth, Thomas A1 - Eliezer, D. A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging of deuterium assisted cracking in a 2205 duplex stainless steel microstructure N2 - In the present work, the influence of deuterium on the microstructure of a duplex stainless steel type EN 1.4462 has been characterized by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) supported by scanning electron microscopy (SEM), focused ion beam (FIB), electron back scattered diffraction(EBSD) and energy dispersive x-ray (EDX) investigations. Characterization has been carried out before and after electrochemical charging with deuterium which has been used as a tracer, due to its similar behavior to hydrogen in the steel microstructure. In a first approach, the distribution of the deuterium occurring at temperatures above 58 °C has been visualized. Further it turned out that sub-surface micro blisters are formed in the ferrite-austenite interface, followed by the formation of needle shaped plates and subsequent cracking at the ferrite surface. In the austenite phase, parallel cracking alongside twins and hexagonal close packed (martensitic) regions has been observed. In both phases and even in the apparent interface, cracking has been associated with high deuterium concentrations, as compared to the surrounding undamaged microstructure. Sub-surface blistering in the ferrite has to be attributed to the accumulation and recombination of deuterium at the ferrite-austenite interface underneath the respective ferrite grains and after fast diffusing through this phase. Generally, the present application of chemometric imaging and structural analyses allows characterization of hydrogen assisted degradation at a sub-micron lateral resolution. KW - ToF-SIMS KW - Hydrogen assisted cracking KW - Hydrogen embrittlement KW - SEM KW - FIB KW - EBSD PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0921509316310334 DO - https://doi.org/10.1016/j.msea.2016.08.107 SN - 0921-5093 VL - 676 SP - 271 EP - 277 PB - Elsevier B.V. AN - OPUS4-37298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nolze, Gert A1 - Winkelmann, A. A1 - Cios, G. A1 - Tokarski, T. T1 - Tetragonality mapping of martensite in high-carbon steel by EBSD N2 - The locally varying tetragonality in martensite grains of a high-carbon steel (1.2 mass percent C) was resolved by electron backscatter diffraction (EBSD) with a spatial resolution in the order of 100 nm. Compared to spatially integrating X-ray diffraction, which yielded an average tetragonality fo c/a=1.05, the EBSD measurements in the scanning electron microscope allowed to image a local variation of the lattice papameter ration c/a in the range of 1.02 ≤ c/a ≤ 1.07. The local variation of tetragonality is confirmed by two different EBSD data analysis approaches based on the fitting of simulated to experimental EBSD patterns. The resulting EBSD-based tetragonality maps are pointing to a complex interaction of carbon concentration and local lattice distortions during the formation process of martensitic structures. KW - EBSD KW - Martensite KW - Tetragonal distortion KW - Pattern matching PY - 2021 DO - https://doi.org/10.1016/j.matchar.2021.111040 VL - 175 SP - 111040 PB - Elsevier Inc. AN - OPUS4-52343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yukhvid, V. A1 - Gorshkov, V. A1 - Miloserdov, P. A1 - Skachkova, N. A1 - Alymov, M. I. A1 - Nolze, Gert A1 - Epishin, A. T1 - Synthesis of Molybdenum and Niobium Mono- and Binary Silicides by the Method of SHS-Metallurgy N2 - The process of self-propagating high-temperature synthesis of the Mo–Nb–Si silicides from the powder mixtures has been investigated. Based on performed experiments, the composition of powder mixtures as well as technological parameters are proposed which provide the synthesis of monosilicides MoSi₂, NbSi₂, and binary silicides Mo₁-хNbxSi₂ with different ratios of Nb/Mo by adding different contents of MoO₃ and Nb₂O₅. Microstructure and phase compositions of the obtained silicide ingots are characterized by scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and backscatter electron diffraction. KW - Synthesis KW - EBSD KW - XRD PY - 2016 DO - https://doi.org/10.1002/adem.201600334 SN - 1438-1656 SN - 1527-2648 SP - 1 EP - 6 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-37209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scheffler, Franziska A1 - Fleck, Mirjam A1 - Busch, Richard A1 - Casado, Santiago A1 - Gnecco, Enrico A1 - Tielemann, Christopher A1 - Brauer, Delia S. A1 - Müller, Ralf T1 - Surface Crystallization of Barium Fresnoite Glass: Annealing Atmosphere, Crystal Morphology and Orientation N2 - Controlled oriented crystallization of glass surfaces is desired for high precision applications, since the uppermost crystal layer significantly influences the properties of the material. In contrast to previous studies, the data presented here deal with separated crystals growing at defect-free surfaces in four atmospheres with different degrees of humidity (ambient/dry air, argon and vacuum). A glass with the composition 2 BaO–TiO2–2.75 SiO2 was heat-treated at 825 °C until fresnoite (Ba2TiSi2O8) grew to a significant size. The crystal growth rate is found to increase with increasing humidity. The morphology of the crystals changes from highly distorted dendrites in the driest atmosphere (vacuum) to circular/spear-head-shaped crystals in the wettest atmosphere (ambient air), which we attribute to a decrease in viscosity of the glass surface due to water uptake. The least distorted crystals appear in the form of depressions of up to 6 µm. This has an influence on the observed crystal orientation, as measured by electron backscatter diffraction (EBSD). The pulled-in crystals change the orientation during growth relative to the flat glass surface due to an enrichment in SiO2 at the crystal fronts. This confirms that the orientation of crystals is not fixed following nucleation. KW - Fresnoite KW - Surface crystallization KW - Crystal growth KW - Crystal morphology KW - Crystal orientation KW - EBSD PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587230 DO - https://doi.org/10.3390/cryst13030475 VL - 13 IS - 3 SP - 1 EP - 17 PB - MDPI AG CY - Basel AN - OPUS4-58723 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dieck, S. A1 - Ecke, M. A1 - Fritsch, S. A1 - Rosemann, Paul A1 - Wagner, M. A1 - Halle, T. T1 - SD effect in martensitic stainless steel under Q&P heat treatment condition N2 - The quenching and partitioning (Q&P) heat treatment enables a higher deformability of high strength martensitic steels. The Q&P heat treatment was applied on the martensitic stainless steel 1.4034 (X46Cr13) to study the influence of partitioning time. Therefore, extensive characterizations of the mechanical properties, focussing on the materials behaviour under different mechanical load scenarios, were performed. A comprehensive analysis of the microstructural evolution was per-formed for different heat treatment and mechanical loading states. A complete solution of chromium carbides was detected to be a first requirement for successful Q&P heat treatment. The comparison of common quenching and tempering with the Q&P heat treatment verifies the extensively enhanced materials strength whereat the formability is still acceptable. The microstructural reason was detected to be an increasing aus-tenite fraction due to austenite reversion at subgrain boundaries of martensite besides the stabilising of retained austenite. Further a distinctive strength differential effect was observed. T2 - 11th European Symposium on Martensitic Transformations CY - Metz, France DA - 27.08.2018 KW - Martensitic stainless steels KW - Heat treatment KW - EBSD KW - Quenching and partitioning KW - TRIP PY - 2018 AN - OPUS4-45803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Busch, R. A1 - Tielemann, Christopher A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Patzig, C. A1 - Krause, M. A1 - Höche, T. T1 - Sample preparation for analytical scanning electron microscopy using initial notch sectioning N2 - A novel method for broad ion beam based sample sectioning using the concept of initial notches is presented. An adapted sample geometry is utilized in order to create terraces with a well-define d step in erosion depth from the surface. The method consists of milling a notch into the surface, followed by glancing-angle ion beam erosion, which leads to preferential erosion at the notch due to increased local surface elevation. The process of terrace formation can be utilized in sample preparation for analytical scanning electron microscopy in order to get efficient access to the depth-dependent microstructure of a material. It is demonstrated that the method can be applied to both conducting and non-conducting specimens. Furthermore, experimental parameters influencing the preparation success are determined. Finally, as a proof-of-concept, an electron backscatter diffraction study on a surface crystallized diopside glass ceramic is performed, where the method is used to analyze orientation dependent crystal growth phenomena occurring during growth of surface crystals into the bulk. KW - 3D etching KW - Ion beam erosion Sectioning KW - EBSD KW - Sample preparation KW - Analytical scanning electron microscopy KW - SEM KW - Glass Ceramic KW - Glass KW - Diopsid PY - 2021 DO - https://doi.org/10.1016/j.micron.2021.103090 SN - 0968-4328 VL - 150 PB - Elsevier B.V. AN - OPUS4-53075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dieck, S. A1 - Ecke, M. A1 - Rosemann, Paul A1 - Halle, T. T1 - Reversed austenite for enhancing ductility of martensitic stainless steel N2 - Quenching and partitioning (Q&P) heat Treatment increases the deformability of high-strength martensitic steels. Therefore, it is necessary to have some metastable austenite in the microstructure, which transforms in martensite during plastic deformation (TRIP effect). The austenitic-martensitic microstructure is gained by an increased austenitization temperature, water quenching and additional partitioning. The partitioning enables local carbon diffusion, which stabilizes retained austenite and leads to partial reversion of martensite to austenite. The influence of partitioning time was studied for the martensitic stainless steel AISI 420 (X46Cr13, 1.4034). In line with these efforts, metallographic, XRD and EBSD measurements were performed to characterize the microstructural evolution. The mechanical properties were tested using tension and compression loading. Additional corrosion investigations showed the benefits of Q&P heat treatment compared to conventional tempering. The reversion of austenite by the partitioning treatment was verified with EBSD and XRD. Furthermore, the results of the mechanical and corrosion testing showed improved properties due to the Q&P heat treatment. T2 - International Conference on Martensitic Transformations CY - Chicago, IL, USA DA - 09.07.2017 KW - Heat treatment KW - High ductility KW - Martensitic stainless steels KW - Quenching and partitioning KW - Transformation induced plasticity KW - KorroPad KW - EBSD KW - Mechanical testing PY - 2018 SN - 978-3-319-76968-4 DO - https://doi.org/10.1007/978-3-319-76968-4_19 SP - 123 EP - 128 PB - Springer AN - OPUS4-44689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Report ISO/TC202/WG4 X-Ray Spectroscopy, Liaisons with VAMAS and ISO/TC229 Nanotechnologies N2 - The presentation is structured in the following three parts: i) Report of the Working Group 4 X-Ray Spectroscopy including the publication of ISO 15632:2021 Microbeam analysis — Selected instrumental performance parameters for the specification and checking of energy-dispersive X-ray spectrometers for use in electron probe microanalysis, ii) Liaison activities between ISO/TC202 Microbeam Anaylsis and VAMAS/TWA34 Quantitative Microstructural Analysis, and iii) Liaison activities from ISO/TC202 Microbeam Analysis for ISO/TC229 Nanotechnologies. Most relevant projects are highlighted for information and further discussions. New initiatives and better promotion of strategic projects are addressed. T2 - Annual Meeting of ISO/TC 202 Microbeam Analysis CY - Online meeting DA - 25.10.2021 KW - Microbeam Analysis KW - VAMAS KW - ISO/TC 202 KW - ISO/TC 229 KW - electron microscopy KW - X-Ray Spectroscopy KW - EBSD KW - FIB PY - 2021 AN - OPUS4-53625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -