Regensburg 2010 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 22: Hydrogen in Metals

MM 22.3: Vortrag

Dienstag, 23. März 2010, 10:45–11:00, H5

Strain-induced metal-hydrogen interactions across the first transition series: An ab initio study of hydrogen embrittlement — •Johann von Pezold, Liverios Lymperakis, and Jörg Neugebauer — Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Deutschland

The attractive interaction between hydrogen and distorted regions of the host matrix underlies all the currently discussed mechanisms of hydrogen-induced embrittlement of metals, such as hydrogen enhanced local plasticity (HELP), hydrogen enhanced decohesion (HEDE) and stress-induced hydride formation. In this study we investigate these interactions systematically by determining heat of solutions, H-H binding energies within the metal matrix, as well as phase diagrams as a function of the lattice strain and the H chemical potential across the first transition series (3d elements) using density functional theory (DFT) calculations. It will be shown that these provide a very direct insight and allow an identification of the likely embrittlement mechanisms within these metals.