Influence of CaO and ZnO Content on the Crystallization and Foaming of CaO―Al2O3―SiO2 Glass―ceramics

CaO―Al2O3―SiO2 system glass were used to produce foam glass―ceramics with high performance. Influence of ZnO and CaO contents on the crystallization and foaming behavior of CaO―Al2O3―SiO2 glass, were investigated using graphite as foaming agent. Addition of ZnO can suppress the crystallization of pseudowollastonite, improve the sintering of the mixture of glass powder and foaming agent, and reduce the combustion―loss of foaming agent at low temperature. Further addition of CaO leads to higher crystallinity, as well as higher glass―viscosity, which will hamper the foaming process and get poorer foaming ability. 18wt% CaO and 6wt% ZnO in CaO―Al2O3―SiO2 glass are helpful to produce foam glass ceramics with high porosity at the sintering temperature of 1000 .