Effect of Alumina Content on Structure and Properties of High Refractive Index Glass

In this paper, BaO-ZnO-TiO₂-SiO₂ is used as the research system of high refractive index glass, and IR, XRD and DTA are used to study the structure, thermal behavior, crystallization and chemical stability of different glasses when Al₂O₃ gradually replaces CaO. The results show that when Al₂O₃ replaces CaO, the glass still has an amorphous structure. With the increase of Al₂O₃ content, the glass structure first becomes tight, and then due to the formation of [AlO₆], the glass network becomes loose, and the glass density peaks with the increase of Al₂O₃ content. DTA analysis showed that with the increase of Al₂O₃ content, the devitrification trend of the glass increased during the cooling process, the crystallization peak moved to the low temperature direction, and the exothermic effect weakened, indicating that the surface crystallization trend of the glass increased and the overall crystallization became weaker. The results show that the density, refractive index and water resistance of glass microspheres containing only CaO are the best, but the crystallization of glass is obvious during heat treatment.