Spherical shape BaO-ZnO-B2O3-SiO2 glass powders prepared by spray pyrolysis

Fine-sized BaO-ZnO-B2O3-SiO2 (BZBS) glass powders were directly prepared by high temperature spray pyrolysis. The hollow glass powders prepared at low preparation temperature of 1000 degrees C had a low density of 2.65 g/cm(3). However, the densities of the BZBS powders obtained at preparation temperatures of 1200 and 1400 degrees C were each 3.92 and 4.13 g/cm(3). The mean size of the BZBS glass powders prepared by spray pyrolysis at preparation temperature of 1400 degrees C was 0.98 mu m. The glass transition temperature (T-g) of the prepared BZBS glass powders was 518.9 degrees C. The dielectric layers formed from the prepared BZBS glass powders with a dense structure had a clean surface and a dense inner structure without voids at the firing temperature of 580 degrees C. The transparencies of the dielectric layers formed from the prepared BZBS glass powders were higher than 90% within the visible range.