Anisotropy of the Vacancy Migration in Ti, Zr and Hf Hexagonal Close-Packed Metals from First Principles

• DOI: 10.4028/www.scientific.net/ssp.129.75
• Publication Date: 2009-03-16T10:30:41Z
• Authors: Guillaume Vérité; F. Willaime; Chu Chun Fu
• Keywords: SIESTA (computer program)

The vacancy properties in group-IV hexagonal close-packed metals (Ti, Zr and Hf) have been investigated by Density Functional Theory (DFT) calculations performed with the SIESTA code. migration energies are found to be systematically lower »0.15 eV within basal plane than out of plane. electronic origin this significant contribution diffusion anisotropy is evidenced analysis local densities states a comparison empirical potential. average value migra- tion energy very good agreement available experimental data Zr. activation for self-diffusion obtained assuming mechanism experiments Hf, although slightly too small, but discrepancy observed Ti.