The principles of nucleation theory relevant to the void swelling problem

The nucleation of small stable species is described in the problem of void growth by discrete rate equations. The purpose of this review is to clarify and draw together existing ideas on incubation dose and critical cavity radius for void nucleation and those of classical nucleation theory. When gas is being produced the problem reduces to one of calculating the incubation dose for the gas bubble-to-void transition. A general expression for the steady state nucleation rate is derived for the case when voids are formed by vacancy fluctuations which enable an effective nucleation barrier to be crossed.