DIFFUSION CONSTANTS FOR THE VACANCY MECHANISM IN MG AND ALPHA-ZR - CALCULATION

Self-diffusion coefficients for the monovacancy mechanism described in terms of the Arrhenius law are calculated in Mg and alpha-Zr from computer simulation results. Different short-range pair interatomic potentials which reproduce some material properties are used. Special interest is devoted to the results obtained for the alpha-Zr lattice; by assuming a vacancy-formation energy value E(f) = 1.8 eV, a self-diffusion energy value Q = 3.3 eV and a pre-exponential factor D0 = 5 x 10(-5) m2 s-1 are obtained. These numbers indirectly support some ideas proposed in the literature to understand the self-diffusion behaviour shown by experimental results, as well as some predictions made by other authors.