Computer simulation of displacement cascades and the defects they generatein metals

Molecular dynamics (MD) computer simulation provides information that canno t be obtained by other means on the primary state of damage due to displace ment cascades ill metals. Progress in a number of topics in this field is r eviewed here. It includes research dealing with the effect on defect format ion in pure metals and alloys of primary knock-on atom (PM) energy and irra diation temperature. Clear views on dependencies and trends have emerged in these areas. In terms of the development of models to describe the evoluti on of radiation damage and its role in phenomena such as irradiation-induce d hardening, creep and swelling, the important parameters are not only the total number of Frenkel defects but also the distribution of their populati on in clusters and the form and mobility of these clusters. Recent results on these aspects are presented and it is shown that computer simulation pro vides detailed information that paves the way for successful development of models of the evolution of damage beyond the stage of the cascade process. (C) 1999 Elsevier Science B.V. All rights reserved.