Densification Study Of Attritor Milled Magnesum Aluminate Spinel

Pre-synthesization of magnesium aluminate spinel was done by mixing magnesium hydroxide and aluminium hydroxide in a molar ratio of Mg0:Al203=1:1 and then calcining the mixture at temperatures between 900 and 1600 deg C. X-ray diffraction patterns confirmed that only spinel phase was present above 1400 deg C. Pre-synthesized spinels were then attritor milled up to 6 hours and the extent of milling was characterized by surface area measurement. Milled and unmilled materials were isostatically pressed at 175 MPa and sintered between 1550 and 1650 deg C for 2 hours and studied for densification. A maximum of 99% densification was achieved at a sintering temperature of 1650 deg C.