Monte Carlo modelling of damage accumulation in metals under cascade irradiation

The Monte Carlo (MC) method is used to study cascade damage effects in dama ge accumulation in pure metals at temperatures below stage III, when vacanc ies and their clusters are immobile. The irradiation is modelled by sequent ial introduction of collections of defects representing the primary damage state of cascades placed randomly in the simulation volume. The cascades ge nerated in molecular dynamics (MD) simulations for recoil energies from 2 t o 10 keV are used. Concentrations of point defects as well as defect cluste r densities are monitored as a function of dose up to 0.02 dpa. The results are compared with those obtained in the mean-field (MF) approximation. Fac tors responsible for the difference in damage accumulation under homogeneou s and cascade irradiation conditions are revealed. Problems in using MC mod elling to study damage accumulation when interstitial clusters move one-dim ensionally are investigated and discussed. (C) 2000 Elsevier Science B.V. A ll rights reserved.