Structure and properties of the lithium aluminosilicate glasses with yttria addition

The structure and properties of lithium aluminosilicate glasses containing Y2O3 were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA) and Raman spectroscopy. Effects of yttria on the viscosity of LAS glasses were investigated, and found that the introduction of yttria effectively decreased the viscosity of LAS glasses. In Raman spectra of initial glasses it is shown the starting glasses are in almost complete disorder, since all bands are weak and broad. In the spectra of heat-treated specimens some new narrow bands appear and increase in intensity, and the frequency changes with varied yttria addition. The DTA and XRD results show that yttria controlled the crystallization of LAS glasses by increasing the crystallization peak temperature (Tp), however, the main crystalline phase of glass-ceramics was β-spodumene.