Effect of addition of Cr2O3 on the properties of reaction sintered MgO–Al2O3 spinels

Effect of addition of Cr2O3 up to 4 wt.% was studied on three different spinel compositions with MgO:Al2O3 molar ratios 2:1, 1:1 and 1:2. Attritor mill was used to reduce the particle size of the starting materials and a single stage sintering technique was employed in the temperature range of 1550–1650 °C for all the compositions. Final sintered products were then characterised in terms of densification and shrinkage studies, phase analysis, strength evaluation both at the ambient temperature and at 1300 °C, strength retention capacity after different cycles of thermal shock at 1000 °C, quantitative elemental analysis and microstructural studies.