Microstructure and Properties of TiSi_2-based Composites in situ Prepared by SPS

TiSi_2-SiC and TiSi_2-SiC-Ti_3SiC_2 composites were in situ fabricated by spark plasma sin- tering using commercially available Si,Ti,C and TiC as starting materials.The phase constitutes and microstructures of the composites were analyzed by XRD,FESEM and TEM.It shows that the TiSi_2 grains are larger than lpm and SiC particles in the range of 200-300nm uniformly distribute in the TiSi_2 matrix.The hardness,fracture toughness and bending strength of TiSi_2-SiC composites increase with the SiC contents increasing.The introduction of Ti_3SiC_2 enhances the mechanical properties of TiSi_2-SiC-Ti_3SiC_2 composite greatly.In addition,the introduction of SiC and Ti_3SiC_2 have little effect on the electrical conductivity and thermal conductivity of TiSi_2-SiC composites tested at the elevated temperature.