An investigation was made of the dynamics of nucleation and the growth of voids in an irradiated material in the presence of a spatially heterogeneous dislocation microstructure. It was found that, due to the sensitivity of the void nucleation rate to the local vacancy supersaturation, voids nucleated and grew almost exclusively in regions where the density of dislocations was low. Numerical simulations showed that the relatively high void growth rates which were observed experimentally in regions of low dislocation density - leading to the segregated evolution of dislocations and voids - could be described by the solutions of a spatially heterogeneous reaction-diffusion model that took continuous nucleation of voids into account but did not assume the occurrence of long-range 1-dimensional transport of clusters of self-interstitial atoms through the material.

Segregation of Voids in a Spatially Heterogeneous Dislocation Microstructure. S.L.Dudarev, A.A.Semenov, C.H.Woo: Physical Review B, 2004, 70[9], 094115 (8pp)