MOLECULAR-DYNAMICS SIMULATIONS OF THE SELF-DIFFUSION PHENOMENA IN NI2Y INTERMETALLIC PHASE

We present a molecular dynamics study of the diffusion phenomena in Ni 2Y, transition-metal intermetallic phase via nearly-free-electron-tigh t-binding-bond interatomic interaction model. Interpretations of the d ynamic structures from the calculations of the mean square displacemen ts and spectral densities of velocity show that the rapid growth of th is intermetallic phase found in the experimental study is mainly due t o the high-rate self-diffusion in and near the grain-boundaries and in dependent of the vacancy. Therefore, the standard vacancy-based diffus ion process is found to be not essential in this phase. (C) 1998 Elsev ier Science S.A. All rights reserved.