Short carbon fibre (C f ) reinforced TiCN-based cermets (C f /TiCN composites) were produced by powder metallurgy method with pressureless sintering technology. The phase evolution, microstructure and fracture morphology of C f /TiCN composites were investigated. The results showed that TiC, TiN, WC, Cr 3 C 2 and Mo phases disappeared gradually and diffused into core and rim phases by dissolution-reprecipitation process, finally formed new hard TiCN core phases and complex compound (Cr, W, Mo, Ti)(CN) rim phases, with the sintering temperature increasing. The added C f did not change the 'core-rim' microstructure but improved the mechanical properties of TiCN-based cermets. The C f /TiCN composite containing 3 wt-% C f achieved the best comprehensive mechanical properties, with fracture toughness and bending strength increasing by about 14.4% and 30.8%, respectively, when compared with the composite without C f . Toughening and strengthening mechanisms of C f /TiCN composite were concluded as crack deflection and branch, as well as the pull-out, fracture and bridging of carbon fibres.

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