Prediction of the behaviour of ZrC particles in a Zr-2.5 wt% Nb alloy under irradiation

Particles of ZrC may be present in the Zr-2.5 wt% Nb alloy of the pressure tubes of CANDU-PHW nuclear reactors. Knowledge of the evolution under irradiation of these particles is important to predict the in service behaviour of those components. In this letter, that evolution is analysed considering the distribution of precipitates of ZrC obtained by Piotrkowski et al. in the same alloy without irradiation, as the initial state of the material. It is also assumed that the processes involved are controlled by the interstitial carbon diffusion, which is not strongly affected by the irradiation. The model of particle stability with recoil resolution proposed by Frost and Russell is used here and is presently summarized. (orig.)