In order to study enivironmentally-assisted cracking mechanism of stainless steel under BWR primary coolant condition, effects of applied load on oxidation in the vicinity of crack tips of CT specimens were evaluated. Loaded CT specimens were immersed in an aqueous condition at 290℃ as a simulated BWR coolant condition, and microstructural observation on oxide near the tips of pre-cracks was carried out. Oxide inner layers, which consisted of fine grain magnetite containing Fe and Cr were formed, and oxide outer layers consisting of large grains of Fe₃O₄ were observed to cover the inner layers. FEM analysis of stress and strain in the loaded CT specimen suggests that both of dislocations due to localized plastic deformation and elastic strain could play important roles to accelerate inner oxide formation in the vicinity of the crack tip of the specimens.

Corrosion of metal cans was examined from the viewpoint of polarization resistance. The relationship between results obtained electrochemically using polarization resistance and judgments from empirical can pack test observations was revealed. After practical experiments using actual can container filled with test solutions changing concentrations of chloride ion and hydrogen ions, both results exactly corresponded. It is discussed that the application of polarization resistance to the traditional can pack test will be a very advantageous tool for easy and rapid determination of can degradation.