Simulations of the diffusion process in ordered B2 NiAl at high temperatures were performed using an embedded atom interatomic potential. Diffusion occurred via a variety of cyclic mechanisms that accomplished the motion of the vacancy through nearest-neighbor jumps; restoring order to the alloy at the end of the cycle. The traditionally postulated 6-jump cycle was just one of the various cycles observed and some of these were quite complex. A detailed sequential analysis of the observed 6-jump cycles was performed and the results were analyzed in terms of the activation energies for individual jumps calculated using molecular statics simulations.

Direct Molecular Dynamics Simulations of Diffusion Mechanisms in NiAl. Farkas, D., Soulé de Bas, B.: Materials Research Society Symposium - Proceedings, 2001, 646, N671-6. See also: Acta Materialia, 2003, 51[5], 1437-46 and Defect and Diffusion Forum, 2003, 213-215, 83-94