Crystallization behavior of WO3-MoO3-TeO2 glasses

Abstract In the present study, crystallization behavior of tungsten molybdenum tellurite glasses was investigated by non-isothermal methods using differential scanning calorimetry (DSC), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) techniques. Thermal properties of glasses were investigated to calculate the values of glass transition temperature ( T g ), crystallization temperature ( T c / T p ), temperature difference (Δ T ), thermal stability ( S ), glass transition activation energy ( E g ) and fragility parameter ( m ). Average cross-link density ( n c ¯ ) values were calculated for the physical investigation of the glasses. The crystallization kinetics was studied at different heating rates and the values of Avrami constant ( n ) and morphology index ( m ) were calculated from the Ozawa equation and the activation energy of crystallization ( E c ) was determined using the modified Kissinger equation. The crystallized and/or transformed phases and their morphologies were determined by XRD and SEM analysis. Studied glass compositions were found to be thermally stable, resistant to crystallization and therefore suitable for opto-electronic applications.