Abstract:
β-Sialon ceramic was prepared by high temperature nitriding reaction of raw material including Al metal powder, Si powder and α-Al
2O
3 fine powder. Adding different mass fractions of Y
2O
3 and TiO
2 as sintering additive, the effect of Y
3+ and Ti
4+ on the composition, lattice parameters, sintering properties and microstructure of crystalline phases was studied and compared. The crystalline phases and microstructure were determined by XRD and SEM, respectively. The lattice parameters of the crystalline phases were estimated by X'Pert Plus software. The phase composition was evaluated by semi-quantification method. The results show that the addition of Y
2O
3 and TiO
2 makes the formation temperature of β-Sialon lower obviously. Adding of Y
2O
3 and TiO
2 has a beneficial effect on the solid solubility of Al
2O
3 dissolving into Si
3N
4, the content and the lattice parameters of β-Sialon phase increase and the sintering properties are improved. Comprehensive analysis shows that Y
2O
3 and TiO
2 promote the sintering properties of β-Sialon ceramic, the formation of pressureless sintered β-Sialon ceramic is possible using low cost TiO
2 powder instead of the conventional rare earth as sintering additives.