Compositional dependence of shear-band dynamics in the Zr-Cu-Al bulk metallic glass system

Abstract

Shear-band velocities of individual shear bands in ZrxCu90-xAl10 (x = 45-65) metallic glasses were investigated as a function of temperature and Zr-content. The apparent activation energy of the shear-band propagation dynamics increases with Zr-content, giving evidence for the sensitivity of inhomogeneous plastic flow and related time scales to chemical composition. The shear-band viscosities derived display a Zr-content trend which contrasts with equilibrium viscosities in the supercooled liquid regime. These findings are discussed in terms of effective temperature and short-range order. (C) 2014 AIP Publishing LLC.