FFECTS OF DIFFERENT Li₂O/Al₂O₃ RATIOS ON THE STRUCTURE, PHASE COMPOSITION, AND PROPERTIES OF Li₂O-Al₂O₃-SiO₂ Glass-Ceramics

Abstract

In this study, the effects of different Li₂O/Al₂O₃ ratios on the structure, phase composition and properties of Li₂O-Al₂O₃-SiO₂ glass-ceramics were investigated. The crystallisation behaviour and structure of the glass samples were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM) and other characterisation methods. When the Li₂O/Al₂O₃ ratio (wt.%) was increased from 0.89 to 2.4, the main crystalline phase changed from quartz to a lithium disilicate (LD) phase, indicating that a high Li₂O/Al₂O₃ ratio (wt.%) was more favourable for the precipitation of the LD phase. Finally, a glass-ceramic with a flexural strength of 199 ± 5 MPa, a microhardness of 767 ± 20 HV and a visible light transmission rate of 80% at 550 nm was obtained. Owing to its high Li+ content, this glass-ceramic facilitates chemical strengthening to further improve its mechanical properties and expand its range of applications, such as in electronic display devices.

Keywords

• phase composition
• li₂o/al₂o₃ ratios
• glass-ceramics
• lithium disilicate