Influence of CaO and ZnO Content on the Crystallization and Foaming of CaO-Al_2O_3-SiO_2 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℃.