Abstract
The solid state amorphization of a Ni-Zr diffusion couple subjected to impulsive plastic deformation has been studied in the presence, at the Ni-Zr interface, of an amorphous layer a few nm thick. Previous experiments have shown that the effective interdiffusion coefficient in the metallic glass is strongly enhanced by the deformation process with a resulting fast growth of the amorphous phase during codeformation of elemental couples. If a relaxed glassy film is already present at the interface, the main effect of the deformation is a reduction of the film thickness. Careful observation of the amorphous phase-crystalline Zr interface reveals local thickness variations suggesting that both deformation and fast diffusion occur inhomogeneously in thin shear bands, as expected for a relaxed metallic glass deformed at the strain rates of the present experiment.