Phase-Field Modelling of Void Evolution in Binary Alloys Under Irradiation

The formation and growth of voids have significant influence on the dimensional changes of nuclear materials subjected to irradiation. In this paper, we developed a phase-field model to investigate the evolution of voids in binary alloys under irradiation, which includes the process of irradiation-induced defect formation and annihilation. The relationship of alloy composition and defect formation energy was determined. The nucleation and growth of voids for various alloy compositions were simulated to investigate the effect of solute composition on the void growth kinetics. Our simulation results indicate that, the composition of matrix phase and its influence on the formation energy of vacancy are essential for the growth kinetics and void distribution during irradiation. As an example, the void nucleation and growth in U-Zr alloys are also studied and consistence between the present results and experimental observations were obtained.