In situ synthesis and mechanical properties of bulk Ti3SiC2/TiC composites by SHS/PHIP

Ti3SiC2/TiC composites were synthesized by self-propagating high temperature combustion synthesis with pseudo-hot isostatic pressing procedure (SHS/PHIP) from titanium, silicon, silicon carbide and carbon black powders. The phase and crystal structures were investigated by X-ray diffraction (XRD), and scanning electron microscope (SEM). The results show that the volume fraction of Ti3SiC2 varies with the increasing amount of silicon carbide in the raw material, peaking at 85.4%. The flexural strength increases from 411 ± 17.9 MPa to 547 ± 17.9 MPa with the increasing amount of silicon carbide. However, there is no significant change in compressive strength and fracture toughness. The Vickers hardness of composites varies as a function of applied loads and increases with the increase of relative density. The fracture and damage mechanisms were also discussed.