Non-isothermal crystallization kinetics of \(Cd_{10} Se_{90}\) chalcogenide glass

Abstract

The structure and kinetics of the crystallization reaction of amorphous \(Cd_{10} Se_{90}\) were studied at different heating rates (5–30 K/min) under non-isothermal conditionsby X-ray powder diffraction, scanning electron microscopy (SEM) and differential thermal analysis (DTA) techniques. The Johnson–Mehl–Avrami(JMA) and isoconversional models were used to describe the DTA crystallization data.A strong heating rate dependence of the activation energy was observed when the data were analyzed using Matusita method. This variation of the activation energy was confirmed by the application of the isoconversional methods of Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), Tang, Starink, and Friedman. These methods showed that the activation energy of crystallization is not constant but varies with the degree of conversion and hence with temperature. This variation indicates that the transformation from amorphous to crystalline phase is a complex process involving different mechanisms of nucleation and growth.