Thermal shock damage of the self-reinforced α-SiAlON ceramic using barium aluminosilicate glass ceramic as the sintering additive

Dy–α-SiAlON (Dy1/3Si10Al2ON15) using 5 wt.% BaAl2Si2O8 (BAS) glass ceramic as an additive was synthesized by hot-pressing. The thermal shock resistance of the material was investigated. The results indicated that this material has very good thermal shock resistance. The critical temperature difference could reach 1100 °C. The gradual growth of the pre-existent cracks and the significant interfacial debonding between the SiAlON grains and the intergranular BAS phase were the reasons for the flexure strength losses at the thermal shock temperature difference below and above 1100 °C, respectively. The slight oxidation introduced by the heating process marginally benefited the residual strength by surface damage healing.