Thermal expansion and infrared studies of binary Bi2O3-B2O3 and ternary Bi2O3-B2O3-PbO glasses

The thermal expansion of some binary Bi2O3.B2O3 glasses was measured over a wide composition varying from 30 to 70 wt% Bi2O3 and includes two crystalline products containing 80 and 90% bismuth oxide. Also the measurements were extended to some ternary Bi2O3. B2O3. PbO glasses. The expansion curves for all glasses showed nearly similar behaviour The dilatometric softening point increased with the increase of B2O3 content in binary Bi2O3.B2O3 glasses. In ternary Bi2O3.B2O3.PbO glasses, the softening point decreased first with the increase of PbO and then almost attained constant values. The expansion data are explained by considering various parameters affecting the expansion such as bond strengths, ionic sizes of the respective cations and the probable structural arrangements in such glasses. Also the densities of glasses were measured and the results obtained were used to confirm the compactness and flexibility of the glass structure with composition. Infrared spectroscopy of the glasses were measured and evaluated to confirm the internal structure arrangements of the building units in such glasses. Also, the absorption spectra were measured after subjecting the glasses to an accumulated dose of gamma-rays and showed minor variation of the main structural building groups. The effects of rays was discussed.