%A MIAO Lifeng, JIANG Weihui, BAO Zhenhong %T Preparation and Microstructure of High-alumina Reinforced Hard Porcelain %0 Journal Article %D 2021 %J Materials Reports %R 10.11896/cldb.20070163 %P 24057-24061 %V 35 %N 24 %U {http://www.mater-rep.com/CN/abstract/article_4530.shtml} %8 2021-12-25 %X Based on the traditional hard porcelain formula, high-alumina reinforced hard porcelain with good translucency was prepared by increasing the content of alumina in the formula and using calcined talc and calcite instead of potassium feldspar as flux at 1410 ℃. The effects of MgO, CaO and MgO,CaO composite on the microstructure and properties of hard porcelain were investigated by SEM, XRD, electronic universal testing machine and UV-Vis spectrophotometer, and the mechanism was also discussed. The results show that replacing K2O with MgO or CaO as a flux can eliminate the residual corundum phase and promote the formation of secondary whisker mullite crystals in the porcelain body. However, excessive substitution will lead to the coarsening of mullite whiskers. On the one hand, the introduction of MgO and CaO eliminates the corundum phase with high refractive index, so that a large number of well-developed and uniformly distributed mullite whiskers are formed in the sample. On the other hand, the addition of MgO and CaO improves the refractive index of the glass phase in the porcelain body,reduces the refractive index difference between the crystal phase and the glass phase, and makes the hard porcelain have both high strength and good translucency. With the increase of MgO/CaO mass ratio, the strength of the sample increases first and then decreases, the transmittance increases, and the water absorption decreases gradually. When the MgO/CaO mass ratio is 0.83, the sample has the best comprehensive properties, which has bending strength of 107.3 MPa, light transmittance of 12.6% (1 mm thickness) and water absorption of 0.20%.