Short time oxidation behavior of 308L weld metal and 316L stainless steel with different surface state in simulated primary water with 0.1 mg/L dissolved oxygen

摘要

Many failures in nuclear safe-end dissimilar metal weld joint (DMWJ) have revealed that stress corrosion cracking (SCC) is mainly located in the weld metal (WM). Since the oxide film formed on the stainless steel during service plays an important role in SCC, this research focuses on the short time oxidation behavior of 308 L WM with different surface state in the simulated primary water of pressurized water reactors (PWRs) with 0.1 mg/L dissolved oxygen (DO). In the meanwhile, the oxidation behavior of the 316 L stainless steel with different surface state under the same environmental condition is also studied. Surface state and oxide films are analyzed using various methods. The results show that a dual layered oxide film is formed on 308L WM and 316 L surfaces. Both the cold-worked layer and the surface topography should be considered together when discussing the effects of the surface state on the morphologies of the oxide films.