Micromechanical Characteristics of SCC Crack Tip in Multilayer Oxide Film

Based on oxide film rupture model and photoelectric chemical method conclusion,the micromechanical state of the stress corrosion cracking (SCC) crack tip in the multilayer oxide film on surface of 316 stainless steel was analyzed by finite element method in high temperature water environment.The results show that the high stress-strain field at crack tip mainly concentrated in Fe₃O₄ layer of oxide film.There was a stress-strain mutation at the boundary of different material layers in multilayer oxide film.High stress in the Cr₂O₃ layer and the nickel rich layer was one of the main reasons for decreasing the strength of oxide film and brittle fracture.