Preparation and properties of TaC/Ti₃SiC₂ composites

TaC/Ti₃SiC₂ composites were prepared by reactive hot-pressed sintering.Effects of TaC content on the phase composition, microstructure, mechanical properties and oxidation resistance of TaC/Ti₃SiC₂ composites were investigated by means of X-ray diffraction analysis, scanning electronic microscopy, energy disperse spectroscopy and thermogravimetry.The results show that dense TaC/Ti₃SiC₂ composites can be prepared by reactive hot-pressed sintering.The main phases are Ti₃SiC₂ and TaTiC₂, minor phase is TiC.The bending strength and fracture toughness of TaC/Ti₃SiC₂ composites increase firstly and then decrease with TaC content increasing, and reach the maximum value when the content of TaC is 30wt%.The bending strength and fracture toughness of the composite are 404 MPa and 4.10 MPa·m^1/2, respectively.The addition of TaC makes TaC/Ti₃SiC₂ composites possess superior oxidation resistance than Ti₃SiC.