Evaluation of self-interstitial properties in HCP zirconium using a computer simulation

The self-interstitial properties in hcp zirconium are investigated using dynamical-method computer simulations. The most stable self-interstitial is found to be located at the centroid of the open triangle in the basal plane, while the next most stable one is a crowdion type located at the point between two nearest-neighbor atoms in successive basal planes. Experimental results of annealing of radiation damage and He+ back-scattering also suggest that the two types of configurations are the most possible candidates for self-interstitial in hcp zirconium. Based on the analysis on the configurations and the migration processes of self-interstitials, the recombination coefficients of vacancies and interstitials are evaluated. (orig.)