Effect of replacement of B2O3 by ZnO on preparation and properties of transparent cordierite-based glass-ceramics

• Effect of replacement of B2O3 by ZnO on properties of transparent cordierite-based glass-ceramics was investigated.
• The crystal phases, crystallinity and grain size were affected by the ZnO additives.
• ZnO greatly influenced the optical, physical and thermal properties of glass-ceramics.

The effect of B2O3 replacement by different contents of ZnO on the preparation and various properties of transparent cordierite-based glass-ceramics was deeply investigated. With ZnO addition, the glass transition temperature (Tg) changed slightly, while the crystallization temperature (Tc) decreased greatly, which was confirmed by the DSC results. According to the X-ray diffraction and TEM analysis, ZnO affected the type of the crystal phases, as well as increased the crystallinity and changed the grain size. In addition, the transmittance, thermal expansion coefficient, Vickers hardness and bending strength of glass-ceramics were greatly influenced by the content of ZnO. Transparent glass-ceramics with excellent optical, thermal and physical properties were prepared by nucleating the sample with 2 mol% ZnO content at 820 °C for 6 h and then crystallizing it at 1000 °C for 6 h.