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- The composites were fabricated respectively 61vol.%β-SiC and 39vol.% TiB2 spray-dried powders with the liquid forming additives of 12wt% Al2O3+Y2O3 by pressureless annealing at 1700℃, 1750℃, 1800℃ for 4 hours. The result of phase analysis of composites by XRD revealed α-SiC(6H), TiB2, and YAG(Al5Y3O12) crystal phase. The relative density, the Young's modulus and fracture toughness showed respectively the highest value of 92.97%, 92.88Gpa and 4.4Mpaㆍm½ for composites by pressureless annealing temperature 1700℃ at room temperature. The electrical resistivity showed the lowest value of 8.09×10-3Ωㆍ㎝ for composite by pressureless annealing temperature 1700℃ at 25℃. The electrical resistivity of the SiC-TiB2 composites was all positive temperature cofficient resistance(PTCR) in the temperature ranges from 25℃ to 700℃.