Kinetics of Phase Transformations and Thermal Stability of Ge_xSe₇₀Sb_30-x (x = 5, 10, 15, 20) Chalcogenide Glasses

Abstract

Kinetic studies of two-phase transformations i.e. glass transition and crystallization for Ge x Se 70 Sb 30-x (x = 5, 10, 15, 20) glasses have been performed using differential scanning calorimetry (DSC) at different heating rates under non-iso thermal condition. The glass transition and crystallization regions have been investigated in terms of their characteristic temperatures i.e. glass transition temperature T g and crystallization temperature T c and activation energy. The activation energies of glass transition and crystallization have been calculated by employing peak shift method of Kissinger and isoconversional methods. Activation energies have been found to be dependent on the composition. The thermal stabili - ty is determined from the temperature difference Δ T = T c — T g where T c and T g are the onset crystallization and glass transition temperature respectively. It has been found that Ge 15 Se 70 Sb 15 glass is thermally more stable as compared to the other members of the series.