（1. School of Materials Science and Engineering, Jiujiang University, Jiujiang 332005, China;
2. Jiangxi Province Engineering Research Center of Materials Surface Enhancing & Remanufacturing, Jiujiang
332005, China）
Abstract：With magnesium hydroxide and alumina as raw materials, magnesium alumina spinel was synthesized
by solid phase sintering. The effect of additive BaO on the sintering density of magnesia alumina spinel was stud‐
ied. The effects of additives on the phase composition, sintering property and microstructure of the samples were
analyzed by XRD and SEM. The results show that the addition of BaO can increase the bulk density and linear
shrinkage of Mg-Al spinel after sintering. At the same time, the apparent porosity can be reduced and the sintering
property can be improved. With the increase of additive BaO, the granules of magnesia-alumina spinel increase
first and then decrease. The linear shrinkage rate, apparent porosity and volume density of ?20 mm ×20 mm cylin‐
drical samples sintered at 1 600 ℃×3 h are 6.81%, 54.30% and 1.65g/cm3 without adding BaO. When the amount
of BaO is 0.5%, the linear shrinkage rate, apparent porosity and volume density of ?20 mm ×20 mm cylindrical
samples sintered at 1 600 ℃×3 h are 6.81%, 54.30% and 1.65 g/cm3 respectively. The linear shrinkage rate can
reach 12.07%, the volume density can reach 1.80 g/cm3, and the apparent porosity can reduce to 47.56%. There‐
fore, when the additive content is 0.5%, the sintering property of MgAl2O4 is the best.
2024, Vol. 34 
