Thermal Shock Resistance of Bauxite-based β-Sialon Bonded Corundum Materials

Thermal shock resistant properties of reaction sintered bauxite-based β-Sialon bonded corundum have been investigated, and the results are compared with those of Al2 O3 based counterpart. It is found they all have very good thermal shock resistance. Their residual strength ratios after one thermal shock cycle at △T =1200℃ and △T = 1350℃ are 61% ～73% and 53% ～65% respectively. Their critical temperature difference (TSR) is 600℃～800℃. TSR parameters are calculated based on thermal expansion, modulus of elasticity,and fracture toughness determined. The reasons for improving TSR of these composite materials are discussed.