Abstract
In this paper, constant tensile load tests under simulated primary water environment in boiling water reactor are carried out for sensitized stainless steel type 304 to evaluate influence of applied load and loading time on crack initiation and coalescence behavior by SCC. As a result, many stress corrosion cracks initiated is observed on the smooth surface of specimen, and coalescence of neighboring cracks is also observed. The number of cracks and crack length increase with increasing loading time and applied load. The crack length ranges from 0.02mm to 3.0mm. The crack length which is less than 0.1mm is normal-distributed, and the value of mean and variance of normally distribution are about 50μm and 17μm, respectively.
