Microstructural Design for Improved Mechanical Behaviour of Advanced Materials
J. Phys. IV France 10 (2000) Pr6-179-Pr6-184
Modelling of hydrogen - dislocation interactions during stress corrosion crackingT. Magnin and D. Delafosse
École des Mines, Centre SMS, URA 1884 du CNRS, 158 cours Fauriel, 42023 Saint-Etienne, France
This paper presents a simulation method that is aimed at investigating the elementary mechanisms governing the process of Stress Corrosion Cracking under cathodic hydrogen discharge. Key issues concerning the experimental evidences of localised corrosion - deformation interactions and the relevant modelling are briefly recalled. The simulation method is introduced and the first results on elementary configurations outline the basic mechanisms of hydrogen - plasticity interactions at a Stress Corrosion crack tip. The effect of hydrogen on the density of a dislocation pile-up is examined. The particular situation at the tip of a loaded crack is examined via the introduction of image forces on diffusing interstitial hydrogen. Conclusions are drawn concerning the basic ingredients of the model, as well as future developments of the simulation technique.
© EDP Sciences 2000