Synergistic roles of carbon fibres and ZrO2 particles in strengthening and toughening Li–α–sialon composites

Carbon fibre reinforced Li-α-sialon ceramic matrix composites have been fabricated by a process of slurry infiltration followed by hot-pressing. The roles of both carbon fibres and ZrO2 particles in the strengthening and toughening of Li-α-sialon ceramic matrix composites are discussed. SEM observations show that microcracks in the matrix resulting from the thermal mismatch between the carbon fibres and the matrix can be eliminated by the addition of the ZrO2 and a considerable amount of fibre pullout was achieved during fracture failure of the composites. Measurement of mechanical properties indicates that a synergistic strengthening and toughening has been achieved with bending strength and fracture toughness of ∼410 MPa and ∼12 MPa m1/2 respectively.