Finite element analysis of stress corrosion cracking for copper in an ammoniacal solution

Finite element analyses including a cohesive zone model (CZM) were conducted to investigate the role of corrosion product films (CPFs) in stress corrosion cracking (SCC) for copper in an ammoniacal solution. It is found that a tensile CPF-induced stress generates near the interface between the CPF and the copper substrate at the substrate side in front of the notch tip for a U-shaped edge-notched specimens. The CPF-induced stress is superimposed on the applied stress to enhance emission and motion of dislocations. The peak opening stress (S ₁₁) increases with an increase in CPF thickness and a decrease in CPF Young’s modulus. Damage mechanics based on the CZM was applied to study the stress corrosion crack initiation and propagation by analyzing the stress redistributions and load–displacement curves. The results show that the crack initiates first in the CPF and then propagates to the copper substrate. The fracture strain of the specimen covered a CPF is lower than that without a CPF. Based on the simulation results, the mechanism of the CPF-induced SCC, which promoted the initiation and propagation of the stress corrosion cracks, was discussed.