Molecular Dynamics Simulation of Dealloyed Layer-induced Tensile Stress in Cu3Au

During stress corrosion cracking of Cu3Au alloy, there is a dealloyed layer on its surface because of preferential dissolution of Cu, and there is a linear distribution of Cu vacancy concentration in the dealloyed layer. Molecular dynamics simulation has been done on the three-dimensional crystal (about 14 8000 atomss) by employing the embedded-atom method (EAM) potential. Simulation shows that Cu3Au crystal in which there is a dealloyed layer on one surface and one end is fixed will be deflected after relaxing the a long time because of a tensile stress generated at or near the dealloyed layer interface. The deflection and then the tensile stress increase with increasing the depth of dealloyed layer and the vacancy concentration in the dealloyed layer.