Mechanical properties and oxidation behavior of SiCf/Ti3SiC2 composites prepared by hot isostatic pressing

Abstract SiC f /Ti 3 SiC 2 composites were fabricated by hot isostatic pressing using Ti 3 SiC 2 powder and SiC f as starting materials at 1200°C for 2 h. A maximum flexural strength of 498 MPa and a fracture toughness of 6.76 MPa·m 1/2 were achieved for a composite with 5 vol% SiC f and the microhardness reached 1068 HV 1 with 25 vol% SiC f . SiC and Ti 3 SiC 2 are thermodynamically stable according to the Ti–Si–C phase diagram. However, microstructure analysis showed that the SiC f was distributed uniformly in the Ti 3 SiC 2 matrix with an interfacial layer that was composed of TiC and SiC. Elemental Al agglomeration in the Ti 3 SiC 2 matrix occurred in this reaction layer, which was considered the inducing factor for the occurrence of the interfacial reaction. The interfacial reaction was intense with a low fiber content. Oxidation testing suggested that the oxidation rate increased with SiC f introduction. The oxidation mass gain curve plateaued after 15 h.