Microstructure Characterization and Mechanical Properties of TiSi₂–SiC–Ti₃SiC₂ Composites Prepared by Spark Plasma Sintering

Abstract

Dense TiSi₂–SiC and TiSi₂–SiC–Ti₃SiC₂ composites in which SiC particles in 200–300 nm disperse, were reactively synthesized through spark plasma sintering (SPS) technique using TiC, Si, and C powders in micrometer as starting reactants. The phase constituents and microstructures of the samples were analyzed by X-ray diffraction, field emission scanning electron microscopy and transmission emission microscopy. The hardness, fracture toughness and bending strength of TiSi₂–SiC and TiSi₂–SiC–Ti₃SiC₂ composites were tested at room temperature. The fracture toughness and bending strength of TiSi₂–SiC–Ti₃SiC₂ composites reach 5.4±0.3 MPa·m^1⁄2 and 700±50 MPa, respectively. The factors leading to the improvement of the mechanical properties were discussed.