Three-dimensional phase-field modeling of dislocation loop growth behaviors in irradiated materials: Applications in tungsten

Abstract

In this work, we develop a phase-field model to simulate the growth behaviors of the dislocation loop in irradiated tungsten. The model considers the fact that plenty of defect clusters such as dislocation loops and voids are formed by the diffusion and aggregation of self-interstitial atoms (SIAs) and vacancies created by cascade collision damages. The stable void phase and plate-like morphology of the dislocation loop can be reproduced. We then study the effects of the concentration of SIAs, kinetic coefficient, lattice misfit strain energy, applied shear stress, and the type of the dislocation loop on the growth behaviors of the dislocation loops. It is found that the growth rate of the dislocation loop increases with increasing the concentration of SIAs, kinetic coefficient, and applied stress. The current results can help to understand the growth behaviors of dislocation loops in irradiated W and other irradiated materials.