Mechanical properties of hot-pressed Al2O3/SiC composites

Al2O3/SiC composites were prepared by hot pressing with micrometer Al2O3 powders and SiC powders as raw materials. The mechanical properties, including flexural strength, hardness, and fracture toughness were studied. The experimental results showed that flexural strength was enhanced with the density increasing and grain refining. 615 MPa, the highest flexural strength was obtained in 20 wt.%SiC composite sintered at 1735 °C. The fracture toughness increased at first then decreased with SiC content variation. 7.6 MPa m1/2 of the highest fracture toughness was obtained in the composite containing 5 wt.%SiC sintered at 1635 °C.