EFFECT OF VACANCY DISLOCATION LOOPS ON THE VOID SWELLING RATE

The results of the model developed in the preceding paper for evaluating the vacancy dislocation loop density produced by heavy-particle bombardment are applied to the void swelling problem. Approximate expressions for the maximum swelling rate are given which contain the effects of such loops and of self-interstitial injection in self-ion irradiations. The behavior of the swelling rate is derived in the different temperature regimes where vacancy thermal emission, excess interstitial capture or (if appropriate) where self-interstitial injection mainly determine the loop lifetime. An incubation effect in neutron irradiations at low temperatures and the swelling saturation in self-ion bombardments at high doses are analyzed. It is also shown that the results obtained herein provide a rationale for understanding the differing predictions of swelling rates which have been proposed on the basis of prior numerical analysis. © 1979.