Thermal stability of Cu 0.3(SSe 20) 0.7 chalcogenide glass by differential scanning calorimetry

Abstract

Thermal stability of Cu 0..3(SSe 20) 0.7 chalcogenide glass was investigated by differential scanning calorimetry (DSC). The level of stability for first SSe 20 and second Cu 2Se phases of the present glass was estimated by evaluation of the glass criteria: Deitzel first glass criterion, Δ T, Hruby criterion, H r, and Saad and Poulan weighted thermal criteria, H′ and S. The values of these criteria were obtained based on characteristic temperatures such as: the glass transition temperature, T g, the onset temperature of crystallization, T c, the temperature corresponding to the maximum crystallization rate, T p and the melting temperature T m. It was found that the values of Δ T, H r, H′ and S parameters for the first SSe 20 phase is smaller than that of the second Cu 2Se phase. That indicates a greater thermal stability of second Cu 2Se phase. The stability order at different heating rates is Cu 2Se > SSe 20 as revealed also by thermal K r( T) criterion.