Growth Process of Oxide Films Formed on Type 316L Stainless Steel with Work-Hardened Surface Layers under Creviced Bent Beam Test Conditions in High-Temperature Water

抄録

A creviced bent beam (CBB) test was performed on Type 316L stainless steels with work-hardened surface layers in high-temperature water at 561 K. Growth process of the oxide films on the surface was investigated by cross-sectional transmission electron microscope observation. The oxide films were found to consist of an inner Cr-rich layer and an outer layer of Fe₃O₄ particles. The crystal structure of the inner layer changed from a face center cubic to a spinel-type with an increase in CBB test duration. The inner layers showed a cube-on-cube orientation relationship with adjacent austenite grains of the substrates.