Studies on the Eutectic Sintering of MgO and Al2O3

Investgetions were carried out on eutectic sintering of MgO and Al2O3 with a tri-component eutectic made from a mixture of magnesium oxide, aluminium oxide and silica. An intimate mixture of tri-component eutectic with 20.5% MgO, 17.5% Al2O3 and 62% SiO2 was prepared at 1400°C for 2 hours. The densification behaviour and microstructure have been studied on pellets of MgO and Al2O3 using 3, 5, and 10% by wt of the eutectic mixture at temperatures varying from 1350° to 1600°C. The study revealed that 3 and 5 wt % of the eutectic liquid was just sufficient to attain the approximate theoretical density of magnesia and alumina respectively. The shrinkage data ware analysed to understand the mechanism of sintering.