Morphological evolution and growth kinetics of Kirkendall voids in binary alloy system during deformation process—Phase field crystal simulation study
(School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China)
Abstract: The formation and growth of Kirkendall voids in a binary alloy system during deformation process were investigated by phase field crystal model. The simulation results show that Kirkendall voids nucleate preferentially at the interface, and the average size of the voids increases with both the time and strain rate. There is an obvious coalescence of the voids at a large strain rate when the deformation is applied along the interface under both constant and cyclic strain rate conditions. For the cyclic strain rate applied along the interface, the growth exponent of Kirkendall voids increases with increasing the strain rate when the strain rate is larger than 1.0×10-6, while it increases initially and then decreases when the strain rate is smaller than 9.0×10-7. The growth exponent of Kirkendall voids increases initially and then decreases gradually with increasing the length of cyclic period under a square-wave form constant strain rate.
Key words: Kirkendall void; binary alloy; phase field crystal method; growth exponent; deformation