Ab initio atomic-scale modelling of iodine effects on hcp zirconium

摘要: In order to elucidate possible mechanisms of stress corrosion cracking nuclear power plant cladding material, we have investigated the iodine–zirconium interactions using ab initio atomic-scale calculations. We show that for gas pressure estimated during reactor transients, reduction zirconium effective free surface energy induced by adsorption atomic iodine is significant (more than 80%). Furthermore, given partial pressure, basal planes higher prismatic ones, in agreement with experimental observation a cleavage along planes. also diffusion coefficient, and its high value (about 10−6 cm2 s−1 at 600 K) indicates mobile enough follow crack tip experiments reproduced laboratory conditions. Our results clearly rule out influence absorbed process, equilibrium concentration bei...