The formation and selection of self-organized defect microstructure in irradiated materials were analyzed within the framework of a kinetic model for point and clustered defects. Explicit account was taken of the influence of glissile interstitial clusters upon the stability and morphology of the ordered microstructure. Under void growth conditions, it was found that the anisotropic motion of interstitial clusters provided a key element for microstructure morphology selection. In particular, it resulted in the formation of the void lattice in a parallel orientation to the underlying crystal structure; in agreement with experimental observations. It was also found that body-centered cubic and face-centered cubic void lattices developed in body-centered cubic and face-centered cubic crystals, respectively while, in hexagonal close-packed crystals, the voids formed ordered arrays parallel to basal planes. It was also predicted that a face-centered cubic

void lattice was unstable; thus explaining the experimental difficulty of void lattice formation in face-centered cubic crystals.

Effects of Glissile Interstitial Clusters on Microstructure Self-Organization in Irradiated Materials. D.Walgraef, N.M.Ghoniem: Physical Review B, 2003, 67[6], 064103 (10pp)