Effects of ZrO2 on Crystallization of ZnO-Al2O3-SiO2 Glass
Shinji ENDO, Takashi WAKASUGI and Kohei KADONO
Abstract:The effects of ZrO2 on the crystallization behaviors of ZnO-Al2O3-SiO2 glasses were investigated in order to prepare transparent glass ceramics containing ZnAl2O4 nano-crystal. Nucleation in 20ZnO・20Al2O3・60SiO2 glass proceeded vigorously at the temperature range between 775℃ and 825℃. Though a few silicate phases precipitated in as-quenched 20ZnO・20Al2O3・60SiO2 glasses, addition of ZrO2 and nucleation heat treatments promote the precipitation of ZnAl2O4. As a result, a transparent glass ceramic containing ZnAl2O4 nano-crystal was obtained by crystallization of 20ZnO・20Al2O3・54SiO2・6ZrO2 glass after the heat-treatment at 775℃ for 24 hr. Key Words:Crystallization, Nucleation, Glass ceramics, DTA, ZnAl2O4, Transparency