Phase-field modeling of interaction between void and grain boundaries and its swelling effect

The interaction of irradiated voids and grain boundaries in zirconium is systematically studied by using a composite multiphase-field model that couples the evolution of irradiated voids and grain boundaries. In phase-field modeling, the polycrystalline evolution phase-field governing equation and void evolution phase-field governing equation are coupled together for modeling. In the numerical solution, the aforementioned two sets of equations are coupled to solve the absorption of vacancies and interstitial atoms by grain boundaries. First, we studied the influence of the existence of voids on the evolution of polycrystalline grains when the voids did not evolve. Thereafter, we examined the influence of the grain boundaries on the evolution of the voids when the grain boundaries did not evolve. Finally, we analyzed the interaction process between the grain boundaries and voids at the same time. The preceding simulation research can reproduce the pinning effect of the void on the grain boundary and the phenomenon that the grain boundary acts on the void evolution process to form a “void-denuded zone” near the grain boundary. The interaction mechanism between grain boundaries and voids is revealed through systematic simulation research. On this basis, the influence of the interaction process between the grain boundary and the void on the swelling behavior is further discussed.