Amorphization and shear microbands near grain boundaries in mechanically alloyed metallic materials.

A theoretical model which effectively describes a novel micromechanism of solid-state amorphization in mechanically alloyed metallic materials is proposed. Within the model the amorphous phase nucleates as a result of the intersection of a grain boundary by a plastic-shear microband. It is shown that the growth of a nucleus of the amorphous α - β alloy near a site on a grain boundary intersected by a shear microband is effectively controlled by the rate of diffusion mixing of atoms of the mechanically alloyed metals α and β. [ABSTRACT FROM AUTHOR]