Enhancement of high-alumina glass and glass-ceramics through dual modification of Zn2+ and its mechanism

In this work, high-alumina glass and glass-ceramics were enhanced through dual modification with Zn2+ and the effects of Zn2+ on the crystallization behavior, structural evolution and properties of high-alumina glass were investigated by a combination of experiments and MD simulation. Firstly, the effect of Zn2+ on the glass network of high-alumina glass was explored using XRD, TEM, SAXS, IR and MD simulation. The results indicate that Zn2+ possesses a dual role of depolymerization and stabilization during the continuous introduction of Zn2+. Secondly, the effects of Zn2+ on the crystallization behavior and structural evolution of high-alumina glass-ceramics were explored using XRD, TEM, SEM, Raman and XPS. It was found that a small amount of Zn2+ would promote the precipitation of nanocrystalline ZnAl2O4 and further enhance the mechanical properties of glass-ceramics. However, a large amount of Zn2+ would lead to the precipitation of the impurity phase SiO2, which could adversely affect the mechanical properties. Finally, the effects of Zn2+ on the properties of high-alumina glass and glass-ceramics were analyzed. The results demonstrated that the mechanical properties and transmittance of high-alumina glass and glass-ceramics can be significantly improved by adding an appropriate amount of Zn2+. Therefore, an effective method based on Zn2+ to modulate the properties of high-alumina glass and glass-ceramics has been successfully developed.