New mechanism for radiation defect production and aggregation in crystalline ceramics

In many ceramic solids, the number of primary displaced ions is different f or different sublattice components, either because the ion masses and displ acement energies differ in simple binary collisions (like in alumina) or be cause radiolytic displacements occur on a single sublattice (like in halide s). However, irradiation produces not only metal colloids or gas precipitat es, but stoichiometric dislocation loops, and voids as well. We propose a s econdary displacement mechanism of vacancy production at a dislocation as a result of its interaction with a primary interstitial ion in another subla ttice which explains the observed phenomena. (C) 2001 Elsevier Science B.V. All rights reserved.