Abstract: CaO-SiO_2-R_2O-F(R=Na,K) glass-ceramic were prepared by sintering method in this paper. Influence of nucleation agent CaF_2 on the crystallization behavior of canasite ceramic glasses had been investigated using differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results indicate that CaF_2 can effectively prompt full crystallization. By means of suitable heat treatment, canasite glass-ceramics can be obtained with a randomly-oriented interlocking blade-like crystals and acicular crystals. The major crystalline phases of the glass-ceramics are canasite and Frankamenite (a fluorine-rich form of canasite). With the increasing of the fluorine concentration, both the content and the number of crystalline phase increase,and the grain size decrease.

Key words: glass-ceramics%canasite%crystallization behavior%microstructure