Continuous amorphization of Cu-Zr studied by positron lifetime and two-dimensional Doppler broadening measurements

摘要

Positron lifetime and 2-dimensional Doppler broadening measurements were used to study the amorphization of Cu_(60)Zr_(40) induced by consecutive folding and rolling. In an intermediate state of folding and rolling cycles a complex microstructure evolves with structural free volumes exhibiting a local environment with enhanced Zr content. In the fully amorphous state after 80 cycles, free volumes of the size of a few missing atoms occur which is contrast to amorphous alloys prepared by melt-spinning.