EFFECT OF PORE COMPOSITION ON THERMAL SHOCK RESISTANCE OF POROUS CERAMICS

Porous alumina ceramics with different pore composition (intrinsic pores and extrinsic pores) were prepared by gel injection molding process combined with pore forming technology and effects of intergranular pores and extrinsic pores on thermal shock fracture resistance and thermal shock damage resistance were studied. The results show that, when the solid phase content or total porosity is the same, the porous ceramic material with extrinsic pores has higher damage tolerance, thermal shock critical temperature difference (ΔTc) and residual strength retention rate. A ratio parameter (KIC/E) for evaluating the thermal shock stability of materials is deduction. The larger the ratio is, the better the thermal shock resistance of materials.