A R₂O-MgO-Al₂O₃-SiO₂ (RMAS, R=Li, Na, K) glaze with low thermal expansion and low content of Li₂O was developed. The effects of Li₂O on structure and properties of the RMAS glaze were studied. The action mechanism of Li₂O was examined by using high temperature microscope, XRD, DTA, FE-SEM and AFM. With increasing content of Li₂O, fluidity of the RMAS glaze decreases first and then increases, while the crystal phase transforms from α-cordierite to α-cordierite and β-eucryptite solid solution (Li_xAl_xSi_3-xO₆). The coefficient of thermal expansion decreases from 3.79×10^-6 ℃^-1 (α_{L20-600 ℃}) to 1.22×10⁻⁶ ℃^-1 (α_{L20-600 ℃}), as the content of Li₂O is increased from 0 wt.% to 2.35 wt.%. When the content of Li₂O is 1.96 wt.%, the RMAS glaze possesses the highest comprehensive properties, with the highest α-cordierite content of 25.5 wt.% and coefficient of thermal expansion of 1.42×10^-6 ℃^-1 (α_{L20-600 ℃}). Compared with that of the sample without Li₂O, the activation energy values for the formation of α-cordierite in the RMAS glaze with 1.96 wt.% Li₂O decreased from 750.6 kJ·mol^-1 to 687.5 kJ·mol^-1.

A series of anorthite-based glass-ceramic glazes with different MgO contents were prepared from kaolin, potash feldspar, quartz, light calcium carbonate and calcined talc, while the effects of MgO content on crystallization, melting properties, microhardness and transparency of the glass-ceramic glazes were studied by using XRD, SEM, EDS and microhardness instrument. When the MgO content was 1.00–2.00 wt.%, the crystalline phase species changed from anorthite and α-pseudowollastonite coexisting with single-phase anorthite. When the MgO content increased from 3.00 wt.% to 5.00 wt.%, the main crystalline phase was still anorthite and the second phase was diopside. In addition, the content of diopside gradually increased. As the MgO content increased from 0.15 wt.% to 5.00 wt.%, the melting properties and transparency of glass-ceramic glazes increased first and then decreased, while the microhardness gradually increased. When the MgO content was 3.00 wt.%, plate-like anorthite with a content of 26.87% precipitated from the glaze and the glaze had excellent transparency and a microhardness of 5.26 GPa.