Crystal plasticity simulation considering oxidation along grain boundary and effect of grain size on stress corrosion cracking

Stress corrosion cracking is a critical concern for light water reactors because it can degrade structural components over a long period. It takes the form of intergranular stress corrosion cracking (IGSCC). Many studies on IGSCC have been conducted over several decades in the past. However, the mechanism of IGSCC initiation and propagation is still not fully understood. In this study, a crystal plasticity model expressing IGSCC is proposed by considering information about the oxidation along the grain boundaries and the failure of an oxide film caused by the localization of a deformation. From a crystal plasticity finite element analysis and an oxygen reaction-diffusion finite difference analysis based on the presented model, the IGSCC is numerically reproduced, and we discuss the effect of grain size on the crack propagation behavior. (author)