Point defect behaviour in irradiated materials

Abstract

When non-fissile materials are bombarded with energetic particles large numbers of vacancies and interstitials are produced. The subsequent behaviour of these point defects is responsible for the observable phenomena of swelling and enhanced creep. In this paper a comprehensive theory of the defect interactions and kinetics leading to swelling and creep is developed. Particular attention is given to determining the densities of point defect sinks, both dislocations and voids, and their dependence on the irradiation temperature. It is shown that the dislocation preference for the capture of interstitials is a strong function of the irradiation temperature and not constant as is frequently assumed. The swelling and creep rates predicted by the theory are shown to be in accord with the experimental results.