Microstructure and ion-exchange properties of glass-ceramics containing ZnAl2O4 and β-quartz solid solution nanocrystals

Crystallization of glass has significant effects on glass structure and the resultant ion-exchange behaviors. In this work, transparent glass-ceramics (GCs) with sequential crystallization of ZnAl2O4 and β-quartz solid solution nanocrystals (NCs) were prepared, and effects of the crystallization on microstructure and ion-exchange properties were investigated. Compared with the specimen with simultaneous precipitation of ZnAl2O4 and β-quartz solid solution NCs, GCs with sequential crystallization of ZnAl2O4 and β-quartz solid solution NCs show smaller grain size and more uniform structure and higher transparency. Ion-exchange depth of layer (DOL) increases significantly with the crystallization of the specimens due to the reduction in content of zinc and five coordinated aluminum in the residual glass matrix. High residual compressive stress and Vickers hardness can be obtained after ion-exchange in KNO3 molten salt.