A PROPOSAL OF STRESS CORROSIN CRACKING MECHANISM FOR EXPLAINING ELONGATION BEHAVIOR OF SOLUTION ANNEALED AUSTENITIC STAINLESS STEELS, TYPE 304 AND TYPE 316

摘要

The stress corrosion cracking mechanism of the solution annealed austenitic stainless steels, type 304 and type 316, is proposed in a qualitative way to explain the effects of applied stress and environmental factors on steady state elongation rate, 1_(ss), with the helps of fracture mechanics, high temperature creep theory and the other SCC mechanisms based upon a film rupture model. The proposed SCC mechanism is forcused on the roles in film formed at crack tip as an obstacle of plastic deformation and in dissolution current as the contribution to plastic deformation through a SCC process. The behaviors of an elongation, a stress and a corrosion current density at crack tips are deduced along with the SCC mechanism.