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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.

Thermal distortion of tailored blanks (TBs) during welding usually leads to a poor formability in the subsequent plastic deformation of TBs, and the welding distortion becomes especially serious in TBs consisting of different thickness plates. In this investigation, finite element method was applied to investigate the welding distortion of TBs with different thickness plates produced by laser beam welding. At the beginning, a 3D heat source model was built and verified by experimental results. Then, the following simulation results showed that the residual stresses generated in the thick plate side of the TBs were higher than those in the thin one. The varied reduction of heat input along the thickness direction for those two base plates can explain for this.

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