| 2007 №09 (04) | 2007 №09 (06) |
The Paton Welding Journal, 2007, #9, 23-27 pages
Mathematical model of transportation of hydrogen by edge dislocation
A.V. Ignatenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Suggested is the model of transportation of hydrogen atoms by edge dislocation, based on the theory of diffusion. An equation of hydrogen diffusion in the field of a moving edge dislocation is proposed, which allows calculation of the amount of hydrogen transported by the dislocation depending upon the metal temperature, velocity of the edge dislocation, and concentration of free hydrogen. As shown by numerical calculations, transfer of hydrogen by the edge dislocation has maximum at a temperature close to the normal one. The results obtained are in good agreement with peculiarities of reversible hydrogen-induced brittleness.
Keywords: arc welding, high-strength steels, welded joints, reversible hydrogen brittleness (RHB), transportation of hydrogen, edge dislocations, temperature and velocity dependence of RHB
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