Ti3SiC2-SiC composites have so far been produced by different methods such as hot-pressing (HP), hot isostatic pressing (HIP), and spark plasma sintering (SPS).Although many attempts have been made to synthesize Ti3SiC2–SiC composites by hot pressing or spark plasma sintering methods, further investigation is required to determine the suitable amount of SiC in which desirable mechanical properties is obtained. Ti3SiC2-SiC composites were fabricated by hot pressing from initial powders of Ti3SiC2 and SiC. The Ti3SiC2-based composites with SiC addition of 10–25% in volume fraction were synthesized to obtain the highest relative density composite. The results show that the highest relative density was related to the Ti3SiC2–20 vol% SiC composite because, according to the diffraction pattern of this sample, due to the high temperature of the hot pressing, the TiC phase was formed by the decomposition of Ti3SiC2. Addition of SiC as the reinforcing phase improved the mechanical properties such as the Vickers hardness of the Ti3SiC2-based composites compared to the monolithic Ti3SiC2, and the highest Vickers hardness value related to the Ti3SiC2–20 vol% SiC composite with the value of 13.882 GPa. Fracture toughness and flexural strength of the Ti3SiC2-based samples were reduced due to the significant difference in the thermal expansion coefficients of Ti3SiC2 and SiC. However, the highest flexural strength was related to the Ti3SiC2–15 vol% SiC composite, due to the presence of TiC phases and low difference of thermal expansion coefficient between Ti3SiC2 and TiC.
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