Thermal and microstructural investigations of oxyfluoride lead germanate glasses

In this study, thermal behaviour and microstructural characterization of germanium rich GeO₂-PbF₂ binary glass system were investigated. The studies were conducted for 10, 20 and 30 mol% PbF₂ contents. The thermal behaviour of oxyfluoride lead germanate glasses was studied using differential thermal analysis (DTA) at the heating rate of 10 °C/min, in air flow. Effects of different heating rates and PbF₂ content were investigated on the glass transition, crystallization and melting temperatures. The structural investigations of as-cast and annealed samples which are heat-treated above crystallization peak temperatures were conducted using X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Utilizing these techniques, α-GeO₂, α-PbGe₄O₉, γ-PbGe₄O₉, PbGeO₃ and Pb₃GeO₅ phases were identified..