Glass-forming region and physical properties of the glasses in the TeO2 − MoO3 − Bi2O3 system

The glass-forming region of the TeO2 − MoO3 − Bi2O3 system was determined by melt quenching method at 850 °C. The nature of crystalline phases formed by heating a mixture of initial oxides up to the predetermined temperature was investigated by X-ray diffraction analysis. The physical properties of glasses were defined and the value of molar volume (Vm), oxygen molar volume (VO), oxygen packing density (ODP), packing density (Vt) and Poisson's ratio were calculated at an equivalent substitution of TeO2 + MoO3 by Bi2O3. DSC curves for series of ternary glasses with different contents of bismuth trioxide were registered and glass transition temperature (Tg), crystallization temperature (Tx) and melting temperature (Tm) were found and the thermal stability range of glasses (ΔT) was calculated. The glass compositions stable to crystallization and suitable for fiber drawing were found.