Self-diffusion of Ni in B2 type intermetallic compound NiAl

Abstract

Combining molecular dynamic (MD) simulation with modified analytic embedded-atom method (MAEAM) potential, the formation, migration and activation energies of Ni self-diffusion in intermetallic compound NiAl have been calculated for five diffusion mechanisms, NNN jump, [1 1 0] 6JC, straight [1 0 0] 6JC, bent [1 0 0] 6JC and triple-defect diffusion. The results show that the Ni self-diffusion is dominated by the triple-defect diffusion mechanism since it requires essentially the lowest migration or activation energy ( Q = 2.769 eV) in the five diffusion mechanisms. This is consistent with the conclusion of Frank et al.