Crystallization, structure and properties of MgO-Al2O3-SiO2 highly crystalline transparent glass-ceramics nucleated by multiple nucleating agents

Generally, highly crystalline transparent glass-ceramics possess excellent physical and chemical properties compared to organic and other inorganic optical materials. We have successfully prepared highly crystalline transparent glass-ceramics in the MgO-Al2O3-SiO2 system by "extreme-time" nucleation & "finite-time" crystallization processes using P2O5, ZrO2 and TiO2 as multiple nucleating agents. The results revealed that the crystallization of glass is controlled by a three-dimensional interfacial crystal growth process. These glass-ceramics mainly consisted of cordierite crystals with a residual glassy phase, and crystallinity increased with crystallization time, but light transmittance decreased with crystallization time due to enlarged grain sizes. EDS mapping revealed a uniform distribution of elements within the glass-ceramic. In the optimal preparation condition (825 °C/96 h + 990 °C/3 h), these glass-ceramics exhibited a high crystallinity (87.3 vol. %), high transmittance (78%), and excellent mechanical properties. This work provides a roadmap for preparing highly crystalline transparent glass-ceramics for applications in optical engineering.