Microstructural regulation and properties enhancement of MgO–CaO ceramics by doping Y2O3

MgO–CaO ceramics with enhanced microhardness and hydration resistance were successfully prepared by doping Y2O3 in this work. The effects of introducing Y2O3 on the microstructure and properties of MgO–CaO ceramics were investigated. The microstructural regulation effects of Y2O3 additive on MgO, CaO, and MgO–CaO ceramics were analyzed comparatively. The results show that Y2O3 dissolves into the CaO lattice to form solid solution in CaO ceramics, and no obvious intergranular phase forms. While the Y2O3 additive leads to the microstructural reconstruction in MgO and MgO–CaO ceramics. By adding Y2O3, SiO2 impurity from magnesium source reacts with CaO to form the silicate phases containing Y3+ ions in MgO–CaO ceramics. The increase in the MgO/CaO interface and the microstructural reconstruction synergistically improves the microhardness and hydration resistance of MgO–CaO ceramics markedly.