It was recalled that, during irradiation, mobile defects, defect clusters and impurity atoms segregated to dislocations. As an external stress was applied, plastic flow was initiated when dislocations were unlocked from segregated defects. Sustained plasticity was achieved by the continuation of dislocation motion; overcoming local forces due to dispersed defects and impurities. Flow localization, post-yield hardening or softening and jerky flow were controlled by dislocation-defect interactions. Computational methods for investigating the dynamics of dislocation-defect interactions were reviewed here. The influence of dislocations upon the motion of glissile self-interstitial atoms and their clusters was explored by using a combination of kinetic Monte Carlo and dislocation dynamics. It was shown that dislocation-decoration by self-interstitial atoms was the result of their 1-dimensional motion and rotation as they approached dislocation cores. The interaction between dislocations and immobilized self-interstitial atom clusters indicated that the unlocking mechanism was dictated by shape instabilities. Computer simulations of the interaction between freed dislocations and stacking-fault tetrahedra in irradiated Cu, and between dislocations and micro-voids in irradiated Fe, were presented. The results exhibited good agreement with experimental observations.

Mechanisms of Dislocation-Defect Interactions in Irradiated Metals Investigated by Computer Simulations. N.M.Ghoniem, S.H.Tong, J.Huang, B.N.Singh, M.Wen: Journal of Nuclear Materials, 2002, 307-311[2], 843-51