Theory of dislocation creep for a material subjected to bombardment by energetic particles role of thermal diffusion

Abstract

The equation for the irradiation creep of a material subjected to bombardment by energetic particles which was developed from continuum mechanics arguments in an earlier paper has now been derived independently from a dislocation model. This reduces the unknowns in the creep equation from two to one. The model, which examines the balance between hardening and recovery, is one which has recently been found to give a reasonable fit to thermal creep data. Its use enables predictions to be made for the irradiation creep rate at around half the absolute temperature of melting. Quite good agreement is found with irradiation-creep data, particularly for a zirconium alloy (Zircaloy 2). The equation is used to define the boundaries between irradiation creep, dislocation creep and diffusion creep on a relaxation-time map for stainless steel.