Effects of Si/Al Molar Ratio on the Properties of Iron-Red Fancy Glaze with Low Thermal Expansion (I)

In this paper, the low thermal expansion iron-red glaze was prepared. Effects of Si/Al molar ratio on the glaze were studied. The phase and thermal expansion coefficient were characterized by XRD and thermal expansion coefficient analysis. The results showed that with the increase of Si/Al molar ratio, the obtained sample changed from small red spots or suitable spots, to connected red spots, and then to little red spots. When Si/Al molar ratio of the sample changes from 8.0 to 9.0, the thermal expansion coefficient of the sample was slightly lower than that of porcelain body and the difference between them remained between 1.08~ 1.12×10^-6K^-1 and 1.16×10^-6K^-1, which indicated that the iron-red glaze could be well matched with the low-expansion porcelain body.