Influence of Nickel-Based Alloys' Mechanical Properties on Mechanochemical Effect at Crack Tip in High Temperature Water Environments

Mechanochemical effect which is the mechanical and chemical interaction can accelerate the stress corrosion cracking (SCC) in nickel-based alloys used in nuclear power plants. The mechanical property heterogeneity in weld joints will influence the mechanochemical effect indirectly. The influences of yield strength and hardening exponent of nickel-based alloy 600 on the mechanochemical effect of crack tip surface in high temperature water environment were studied by adopting one inch compact tension specimen and finite element method. The influence of elastic and plastic deformation on the mechanochemical effect at crack tip was discussed. The results indicate that the mechanochemical effect is affected by the yield strength. In contrary, the hardening exponent change of alloy 600 has an insignificant influence on mechanochemical effect.