Investigation of Kinetics of crystallization Processes of S_(15)-Se_(85), S_(15)-Se_(81)-Cu4 Chalcogenide glasses

摘要

In the present work, S_(15)-Se_(85), S_(15)-Se_(81)-Cu4 chalcogenide glasses are prepared by using conventional melt quenching technique. The as-prepared samples are studied by experimental techniques like X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC). XRD studies have confirmed that the as-prepared samples are amorphous in nature. It is clear from DSC studies that the as-prepared samples are glassy in nature. Kinetic analysis of the crystallization process of as-prepared glasses is carried using DSC curves. Activation energy for glass transition and Activation energy for crystallization are determined using Kissinger method. Activation energy for glass transition of S_(15)-Se_(85) and S_(15)-Se_(81)-Cu4 glasses is found to be 84.5076 and 275.801 KJ/Mole respectively. Activation energy for crystallization of S_(15)-Se_(85) glass is found to be 106.2622 KJ/Mole for 1~(st) peak while Activation energy for crystallization of S_(15)-Se_(81)-Cu4 glasses is found to be 97.93 KJ/Mole for 1~(st) peak and 84.20 KJ/Mole for 2~(nd) peak. Kauzmann temperature (T_k) is determined from the heating rate dependent glass transition and crystallization temperatures. T_k value for S_(15)-Se_(81) glass sample is 236.68°K (1~(st) peak) and for S_(15)-Se_(81)-Cu4 is 283.53°K (1~(st) peak) and 286.33°K (2 peak). Avrami Index (n) is also determined for as-prepared glasses. Avrami Index (n) value for S_(15)-Se_(85) glass sample is 1.8 (1st peak) and for S_(15)-Se_(81)-Cu4 is 2.9 (1~(st) peak) and 1.4 (2~(nd) peak). The crystalline phases by thermal treatment of as-prepared glasses are identified using XRD patterns.