Damage rate dependence of defect cluster nucleation in tungsten during irradiation

Kinetic Monte-Carlo simulations were performed to investigate the damage rate (dpa/s) dependence of void nucleation in tungsten during irradiation. Simulation results indicated that, at temperatures where vacancies can move easily, the void nucleation rate decreases with increasing temperature due to the thermal instability of voids. At relatively high temperatures, no voids were observed unless the damage rate was high enough to nucleate them.