According to a previous dislocation model for void ordering and swelling saturation, these phenomena arose due to the absorption - by voids - of perfect glissile dislocation loops that were produced by irradiation. The formation and glide of small interstitial loops had also been confirmed by molecular dynamics studies of displacement cascades. The cascade mechanism of loop production was shown to explain the absence of visible dislocation loops in some experiments on void lattices, and was an important argument in favor of the theory. However, according to molecular dynamics simulations, the glide of such loops did not seem to depend upon the stacking-fault energy of the host lattice. This was contrary to the predictions of the elastic continuum theory. The latter showed that a high stacking energy favored the unfaulting of small loops. The discrepancy between continuum theory and molecular dynamics simulations indicated a need for further studies of displacement cascades, in particular, in more complex systems that modelled the effects of impurities upon the nature of interstitial clusters. An outstanding problem was that of finding impurities which could facilitate unfaulting and, therefore, void ordering and swelling saturation in metals which were supposed to be void-lattice resistant.

Impact of Glissile Interstitial Loop Production in Cascades on Void Ordering and Swelling Saturation under Irradiation. V.I.Dubinko: Nuclear Instruments & Methods in Physics Research B, 1995, 102[1-4], 125-31