TY - GEN A1 - Dabah, Eitan A1 - Griesche, Axel A1 - Beyer, Katrin A1 - Solórzano, E. A1 - Kannengießer, Thomas ED - Kannengießer, Thomas ED - Babu, S. S. ED - Komizo, Y. ED - Ramirez, A.J. T1 - In situ measurements of hydrogen diffusion in duplex stainless steels by neutron radiography N2 - Hydrogen embrittlement (HE) is a widely known phenomenon and under investigation already for more than a century. This phenomenon, though thoroughly studied, is not yet completely understood, and so far, there are several suggested mechanisms that try to explain the occurrence of HE. One important factor of understanding the HE phenomenon and predicting hydrogen-assisted failure is the descent knowledge about the hydrogen transport behaviour in the material. Neutron radiography is a proven method for tracking hydrogen diffusion and it was applied successfully in various research studies. In the presented study, we examined the hydrogen effusion behaviour in duplex stainless steel by means of neutron radiography and calculated the effective diffusion coefficient from the obtained transmission images. KW - Neutron radiography KW - Hydrogen diffusion KW - Duplex stainless steels KW - Hydrogen embrittlement PY - 2014 SN - 978-3-319-06144-3 SN - 978-3-319-06145-0 U6 - https://doi.org/10.1007/978-3-319-06145-0_9 SP - 155 EP - 163 PB - Springer AN - OPUS4-31357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griesche, Axel A1 - Dabah, Eitan A1 - Kannengießer, Thomas A1 - Hilger, A. A1 - Kardjilov, N. A1 - Manke, I. A1 - Schillinger, B. T1 - MEASURING HYDROGEN DISTRIBUTIONS IN IRON AND STEEL USING NEUTRONS T2 - 10th World Conference on Neutron Radiography (WCNR-10) CY - Grindelwald, Switzerland DA - 2014-10-05 PY - 2014 AN - OPUS4-31666 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griesche, Axel A1 - Dabah, Eitan A1 - Kannengießer, Thomas A1 - Kardjilov, N. A1 - Hilger, A. A1 - Manke, I. T1 - HYDROGEN DISTRIBUTIONS IN IRON VISUALIZED IN 3D BY NEUTRON TOMOGRAPHY T2 - Deutsche Tagung für Forschung mit Synchrotronstrahlung, Neutronen und Ionenstrahlen an Großgeräten 2014 (SNI 2014) CY - Bonn, Germany DA - 2014-09-21 PY - 2014 AN - OPUS4-31667 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Griesche, Axel A1 - Dabah, Eitan A1 - Kardjilov, N. A1 - Hilger, A. A1 - Manke, I. A1 - Kannengießer, Thomas T1 - Imaging of hydrogen in steels using neutrons N2 - We investigated the hydrogen distribution spatially and temporally in technical iron at room temperature. Samples were charged electrochemically and subsequently analysed by means of neutron radiography and tomography. The radiographic images allowed for a time-resolved analysis of hydrogen fluxes. The three-dimensional distribution of hydrogen measured by neutron tomography delivered valuable information for the damage analysis of hydrogen-induced cracks. For the first time hydrogen concentration gradients inside the material could be detect directly together with the cracks. The neutron radiography and tomography results were gained at the Research Reactor BER II of the HZB in Berlin. KW - Hydrogen embrittlement KW - Hydrogen diffusion KW - Neutron tomography KW - Blister PY - 2014 U6 - https://doi.org/10.3139/146.111043 SN - 1862-5282 VL - 105 IS - 7 SP - 640 EP - 644 PB - Carl Hanser CY - München AN - OPUS4-31084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Griesche, Axel A1 - Dabah, Eitan A1 - Kannengießer, Thomas A1 - Kardjilov, N. A1 - Hilger, A. A1 - Manke, I. T1 - Three-dimensional imaging of hydrogen blister in iron with neutron tomography N2 - We investigated hydrogen embrittlement and blistering in electrochemically hydrogen-charged technical iron samples at room temperature. Hydrogen-stimulated cracks and blisters and the corresponding hydrogen distributions were observed by neutron tomography. Cold neutrons were provided by the research reactor BER II to picture the sample with a spatial resolution in the reconstructed three-dimensional model of ~25 µm. We made the unique observation that cracks were filled with molecular hydrogen and that cracks were surrounded by a 50 µm wide zone with a high hydrogen concentration. The zone contains up to ten times more hydrogen than the bulk material. The hydrogen enriched zone can be ascribed to a region of increased local defect density. Hydrogen also accumulated at the sample surface having the highest concentration at blistered areas. The surfaces of the brittle fractured cracks showed micropores visualized by scanning electron microscopy. The micropores were located at grain boundaries and were surrounded by stress fields detected by electron backscattered diffraction. The cracks clearly originated from the micropores. KW - Hydrogen embrittlement KW - Hydrogen diffusion KW - In situ KW - Neutron tomography KW - Iron PY - 2014 U6 - https://doi.org/10.1016/j.actamat.2014.06.034 SN - 1359-6454 SN - 1873-2453 VL - 78 SP - 14 EP - 22 PB - Elsevier Science CY - Kidlington AN - OPUS4-31068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griesche, Axel A1 - Dabah, Eitan A1 - Kannengießer, Thomas A1 - Hilger, A. A1 - Kardjilov, N. A1 - Manke, I. A1 - Schillinger, B. T1 - Imaging of hydrogen in steels using neutrons T2 - Sixth Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 2014-12-03 PY - 2014 AN - OPUS4-32186 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griesche, Axel T1 - Hydrogen in Iron visualized in 3D by neutron tomography N2 - Presented are neutron tomographies on hydrogen charged iron samples. T2 - RACIRI Summer School 2015 CY - Sellin, Rügen, Germany DA - 22.08.2015 KW - Tomographie KW - Wasserstoff KW - Neutronen KW - Hydrogen KW - Neutron KW - Tomography PY - 2014 AN - OPUS4-44838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -