Characterization of activation energy for flow in metallic glasses

Abstract

The molar volume (${V}_{m}$) scaled flow activation energy (\ensuremath{\Delta}$E$), namely as the activation energy density ${\mathbit{\ensuremath{\rho}}}_{E}=\ensuremath{\Delta}E/{V}_{m}$, is proposed to describe the flow of metallic glasses. Based on the energy landscape, both the shear and bulk moduli are critical parameters accounting for the ${\mathbit{\ensuremath{\rho}}}_{E}$ of both homogeneous and inhomogeneous flows in metallic glasses. The expression of ${\mathbit{\ensuremath{\rho}}}_{E}$ is determined experimentally to be a simple expression of ${\ensuremath{\rho}}_{E}=\frac{10}{11}G+\frac{1}{11}K$. The energy density perspective depicts a realistic picture for the flow in metallic glasses and is suggestive for understanding the glass transition and deformation in metallic glasses.