Self-diffusion in several amorphous alloys and in grain boundaries with various orientations was analyzed, and was compared with that in crystals in order to understand better the diffusion mechanisms which operated in disordered structures. An important difference between the diffusion behavior of amorphous alloys and of general grain boundaries on the one hand, and of crystals on the other hand, was a quite different correlation between the pre-factor and the effective activation enthalpy. This correlation was regarded as being the key to determining the validity of alternative diffusion models that were proposed for disordered structures. It was shown that a detailed consideration of the structural disorder, and of the related distribution of energy states of migrating atoms, was necessary in order to understand diffusion in disordered structures.

The Pre-Factor, Do, of the Diffusion Coefficient in Amorphous Alloys and in Grain Boundaries. V.Naundorf, M.P.Macht, A.S.Bakai, N.Lazarev: Journal of Non-Crystalline Solids, 1998, 224[2], 122-34