Effect of the radiation-induced vacancy emission from voids on the void evolution

Recent results of MD simulation have shown that vacancies can be emitted from voids not only by thermal fluctuations (as it is generally conceived) but also by focusing collisions produced under irradiation. A subsequent diffusion of the ejected vacancies away from the void may result in the radiation-induced void dissolution. In the present paper we derive analytical expressions for the rate of the radiation-induced void dissolution under different irradiation conditions and compare it with the rate of void growth due to the biased absorption of vacancies from the bulk. It is shown that the radiation-induced vacancy emission from voids may be responsible for the low temperature (or high dose rate) dissolution of voids and for the saturation of swelling with increasing irradiation dose observed experimentally. (C) 2004 Elsevier B.V. All rights reserved.