Fractographic Study of Stress Corrosion Cracking of SUS 304 Stainless Steel in Various Environment

Abstract

In the previous paper, it was reported that stress corrosion cracking (SCC) of austenitic stainless steels in various environments were divided into the following groups; A group (SCC in the strict sense), Transition group, B group (SCC with corrosion cracking characteristics).
In the present paper, the mechanism of SCC in several groups were studied by fractography. As the results, in A group, fracture planes in SCC were constituted mainly by {100} planes and SCC growth direction was sensitive to the principal stress. In transition group and B group, fracture planes in SCC were constituted mainly by {111} planes. In B group SCC, growth direction was also sensitive to shear stress. The selectivity of the fracture planes and the stress dependency of SCC seem to be closely related to the corrosiveness of environments.