Abstract:
MgO particles coated with Al
2O
3 and TiO
2 precursors, respectively, were prepared by coprecipitation method and sintered at 1 450℃ for 2 h, and then the MgO-based ceramics were obtained. The effects of the addition amount of Al
2O
3 and TiO
2 on the phase composition, sintering performance and thermal shock resistance of the ceramics were investigated. The results show that the ceramics added with Al
2O
3 mainly consisted of periclase and MgAl
2O
4 phases. With increasing Al
2O
3 addition amount, the MgAl
2O
4 phase content increased, the linear shrinkage rate and the number of thermal shock cycles first increased and then decreased, and the bulk density increased. The ceramics added with TiO
2 was mainly composed of periclase, Mg
2TiO
4 and MgTiO
3 phases. With increasing TiO
2 addition amount, the content of Mg
2TiO
4 phase and MgTiO
3 phase increased, the linear shrinkage rate and bulk density first increased and then decreased, and the number of thermal shock cycles first increased and then remained stable. When the mass fractions of Al
2O
3 and TiO
2 were 6%, 4%, respectively, both the sintering performance and thermal shock resistance of the ceramics were the best.