Exploring the impact of Bi2O3 addition on the thermal properties and crystallization behavior of lead borosilicate glasses

Novel heavy-metal oxide glasses with different compositions, specifically (80-x)PbO– xBi2O3–10B2O3–10SiO2, where x ranges from 0 to 60 mol%, were synthesized using a conventional melt-quenching technique. The amorphous nature of these glasses was confirmed through X-ray diffraction analysis. Additionally, infrared spectra were obtained for the prepared samples to explore their structural characteristics. Differential thermal analysis was performed to investigate the characteristic temperatures of the glasses, including the glass transition temperature, melting temperature, onset crystallization temperature, and peak crystallization temperature. The addition of Bi2O3 shifts the characteristic temperatures to higher values and affects the crystallization process and phases formed. Parameters like ΔT, KH, and KSP are used to evaluate and quantify glass stability. Dilatometric measurements demonstrated that substituting PbO with Bi2O3 in the glass composition resulted in an increase in glass transition temperature and dilatometric softening temperature, as well as a decrease in the coefficient of thermal expansion. Furthermore, we determined the density and calculated the molar volume of the samples. These findings deepen our understanding of the thermal behavior, glass stability, and structure-property relationships in lead borosilicate glasses with Bi2O3, facilitating the development and customization of glass compositions with desired thermal and physical characteristics for specific applications.