Calorimetric studies of bulk Se-Te-Pb glassy system

Abstract

Calorimetric studies have been performed on the Se$_{80-x}$ Te₂₀ Pb_x ($0 \leq x\leq 1.4$) samples at different heating rates (5−20 °C/min). The glass transition temperature T_g, the peak crystallization temperature T_p, and the melting temperature T_m are found to increase with increase in heating rate. The apparent activation energies for glass transition E_t and for crystallization E_c have been calculated from the heating rate dependence of T_g and T_p respectively. The effect of Pb addition to the Se-Te matrix on the mechanism of crystal growth has been investigated. The glass transition temperature T_g and the peak crystallization temperature T_p initially decrease with small addition of Pb (x = 0.6) but increases with further addition of Pb (x > 0.6). The thermal stability and glass-forming tendency have also been studied.