Measurements were made of diffusion and thermal relaxation in amorphous samples which had been prepared by melt spinning in vacuum. The diffusivity at 317 to 385C was measured by using Rutherford back-scattering spectrometry. In the case of slowly cooled samples, the results could be described by:

D (cm2/s) = 1.70 x 10-3 exp[-1.55(eV)/kT]

The diffusivities were found to be comparable to the self-diffusivity in crystalline Cu at the same temperatures. However, the activation energies and pre-exponential factors for the amorphous alloy were much lower than those for the crystalline solid. The results suggested that the basic diffusion mechanism in the amorphous alloy might be an extended liquid-like defect that involved 13 or more atoms, rather than monovacancies as in crystalline Cu.

E.C.Stelter, D.Lazarus: Physical Review B, 1987, 36[18], 9545-58