EXPERIMENTAL PHASE STUDIES IN THE TeO2 - WO3 SYSTEM

Tellurite glasses are of great importance in fiber optic amplifying applications and as laser hosts. Comparing with silicate, borate and phosphate glasses, tellurite glasses have superior properties, such as low-phonon energy, high refractive index, high dielectric constant, good corrosion resistance, thermal and chemical stability. TeO(2) is the main but the conditional glass former; therefore, addition of a secondary component, such as heavy metal oxides, increases the glass forming ability. The present study aims to investigate the phase equilibria in the TeO(2) - WO(3) system. Three different compositions, (1-x)TeO(2)-xWO(3) (X = 0.10, 0.15, 0.20 in molar ratio) were prepared. The samples were heated in a platinum crucible for 30 minutes at 750 degrees C, then were quenched and crushed. TG/DTA, XRD and SEM techniques were used to investigate the samples.