| 2007 №08 (01) | 2007 №08 (03) |
The Paton Welding Journal, 2007, #8, 8-11 pages
Mathematical model of reversible hydrogen brittleness
A.V. Ignatenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
A mathematical model of reversible hydrogen brittleness (RHB) of metals with body-centered cubic lattice is proposed. The model is based on classical Siener-Stroh model of microcrack formation in the metal grain by dislocation mechanism, and includes the model of hydrogen transfer by edge dislocations. A programme enabling estimation of the effect of hydrogen on metal grain failure stress was created. In simulating RHB, concentration of free hydrogen in metal, speed of movement of edge dislocations, metal temperature and grain size were taken into account. Calculation-based curves are compared with experimental ones. The dependencies obtained accord well with experimental evidence on RHB.
Keywords: welded structures, reversible hydrogen brittleness, mathematical model, hydrogen transfer, edge dislocations, submicrocrack, degree of embrittlement
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