Correlation between the thermal stability and activation energy of crystallization in metallic glasses

Abstract

The origin of a large spread in the activation energy of crystallization, ΔE, in metallic glasses is explained based on a structural relaxation model. The calculated ΔE from the available thermal and viscosity data is in fair agreement with the experimental results. It is the structural relaxation which leads to high ΔE (⩾100 kcal/mole) for stable glasses. It is also suggested that the structural relaxation is the rate‐controlling factor during the crystallization of the unstable glasses. Thus ΔE for unstable glasses is low (ΔE⩽20 kcal/mole), and is expected to be lower for amorphous metals prepared by low‐temperature deposition than for the corresponding melt‐quenched metallic glasses.