Abstract: The method of differential thermal analysis (DTA) was used to investigate the effect of TiO₂ on the crystallization of CaO-Al₂O₃-SiO₂ system glass.
When TiO₂ is added to the CaO-Al₂O₃-SiO₂ system glass, the glass network becomes more loose, that leads to the viscosity of glass, transition temperature
T_g and crystallization peak temperature T_p decreasing. That the glass is difficult or easy to crystallize does not mean that the crystallization
peak temperature T_p is high or low. Whether the CaO-Al₂O₃-SiO₂ system glass contains TiO₂ or not, the glass mainly begins to crystallize from the surface.
When TiO₂ is used as a nucleation agent, its effect on promoting crystallization is not obvious. After heat-treatment at the nucleation temperature for a long time,
CaO-Al₂O₃-SiO₂ system glass containing TiO₂ still begins to crystallize from the surface, and the more TiO₂ the glass contains, the more obvious the surface crystallization is.

Key words: differential thermal analysis, CaO-Al₂O₃-SiO₂ system glass, crystallization, nucleation agent, heat-treatment