Transparent magnesium aluminosilicate glass-ceramics with high content of ZrO2

Abstract

Magnesium aluminosilicate glass-ceramics are one of the important glass-ceramics with good mechanical performance. However, most of these magnesium aluminosilicate glass-ceramics are colored and non-transparent. In this work, transparent magnesium aluminosilicate glass-ceramics containing ZrO2 are investigated. Devitrification of these magnesium aluminosilicate glass-ceramics is investigated using thermal analysis, X-ray diffraction, Raman spectroscopy, transmission electron microscope, transmission spectra, and Vickers hardness. It is found that crystals precipitated in these glasses and transparency of the glass-ceramics are strongly affected by the concentration of ZrO2. Magnesium aluminosilicate glass-ceramics are found to be nontransparent when the ZrO2 concentration is lower than 6.45 mol.%. With the increase in heat-treatment temperature ZrO2 nanocrystals, MgAl2O4 nanocrystals, and Al6Si2O13 nanocrystals are sequentially precipitated, and Vickers hardness as high as 9.2 GPa are realized in glass-ceramics containing 7.19 mol.% ZrO2.