Original Paper(Vol.61 No.6 pp.509-513)

Composition Dependency of Crystallization ZnO-Al2O3-SiO2-ZrO2 System Glass-Ceramics

Takashi WAKASUGI, Takuma ITO, Yuna GOTO and Kohei KADONO

Abstract:The crystallization behavior of ZnO-Al2O3-SiO2-ZrO2 glasses was investigated by DTA and XRD in order to prepare transparent glass ceramics containing ZnAl2O4 nano-crystal. The crystallization peak temperature (TC) obtained by DTA was used as a measure of the number of nuclei formed in the glass sample during heat treatment. The increase of nucleation rate was observed with the increase of SiO2 and ZnO content. The effects of SiO2 and ZnO to promote their nucleation are different because their effects on the viscosity of glass melts are opposite. The ratio ZnO/Al2O3 is very important to make transparent glass ceramics containing ZnAl2O4 nano-crystal.

Key Words:Crystallization, Nucleation, Glass ceramics, DTA, ZnAl2O4, Transparency