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 T2 - Acta materialia 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. PB - Elsevier Science CY - Kidlington KW - Hydrogen embrittlement KW - Hydrogen diffusion KW - In situ KW - Neutron tomography KW - Iron PY - 2014 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/31068 AN - OPUS4-31068 SN - 1359-6454 SN - 1873-2453 VL - 78 SP - 14 EP - 22 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany