Nonisothermal crystallization kinetics of amorphous Te51.3As45.7Cu3

The structure and kinetics of the crystallization reaction of amorphous Te51.3As45.7Cu3 were studied under nonisothermal conditions using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Two exothermic changes were reported. Five isoconversional methods, of Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO), Tang, Starink, and Vyazovkin, were used to determine the variation of the activation energy for crystallization with temperature, Eα(T). The results show that the activation energy for crystallization associated with the first peak first decreases with increasing temperature and then increases. Different behaviour was observed for the second peak, where an increase of Eα with temperature followed by a decrease. The effect of heating rate on the reaction model, g(α), was also different for the two crystallization peaks.