ZrB 2 –SiC–ZrC nanocomposites containing different contents of ZrC (6–20 wt%) were fabricated by spark plasma synthesizing and sintering method. Sintering mechanism was investigated by studying the displace-ment-temperature-time (DTT) diagrams which were obtained during spark plasma cycles. The flexural strength, hardness and fracture toughness were measured. The mean crystallite size of 77, 62 and 56 nm were calculated respectively for ZrB 2 , SiC and ZrC phases based on the Rietveld method. The maximum relative density (99.8 ± 0.1%), flexural strength (620 ± 24 MPa), Vickers hardness (19.3 ± 0.4 GPa) and fracture toughness (5.7 ± 0.2 MPa m 1/2) were measured for the composite containing 15 wt% ZrC.
