The Crystallization Behaviors of SiO2-Al2O3-CaO-MgO-TiO2 Glass-Ceramic Systems.

To evaluate the crystallization behavior of Ti-bearing blast furnace slag-based glass ceramics, SiO₂-Al₂O₃-CaO-MgO-TiO₂ systems with various TiO₂ were investigated. The crystallization process and mechanical properties were analyzed. The results show that with TiO₂ increasing, exothermic peak temperature (T_p) decreases, and the crystallization is promoted by the introduction of TiO₂. A small amount of TiO₂ (≤4%) addition can significantly promote crystallization, and when TiO₂ continues to increase, the crystallization is decreased slightly. The Avrami parameter (n) of all samples is less than 4, indicating that in prepared glass-ceramics, it is hard to achieve three-dimensional crystal growth. The main crystalline phase is akermanite–gehlenite. The addition of TiO₂ has no obvious effect on the type of main crystalline phase. The prepared glass-ceramic with 4% TiO₂ show good mechanical properties with the hardness values of 542.67 MPa. The recommended content of TiO₂ is 4% for preparing glass-ceramics. [ABSTRACT FROM AUTHOR]