On the nature of enthalpy relaxation below and above the glass transition of metallic glasses

Abstract

Within the framework of the interstitialcy theory, we derived a simple and testable expression for the heat flow (enthalpy relaxation rate) occurring upon warming of glass at a constant rate. Formally, this heat flow is mostly determined by the shear moduli of glass and parent crystal. The underlying physical reason is relaxation of an intrinsic interstitialcy-like defect system. An extensive check of the derived heat flow law for temperatures near the glass transition showed good agreement with the experiment specially performed on two Pd-based metallic glasses.