Ceramics are materials with unique features including high-temperature resistance, high strength, and elastically stiffness, but they suffer from inherent brittleness, low machinability, and thermal shock resistance. Therefore, to tackle these drawbacks, MAX phase ceramics (e.g., Ti2AlC, Ti2AlN, Ti3AlC2, and Ti3SiC2) with a hexagonal structure and combination of properties of both metals and ceramics have recently been produced. These materials are a category of ceramics with a main formula of Mn+1AXn where M represents a transition metal, n = 1, 2 or 3, A is an element belongs to IIIA or IVA groups, and X nominates a nitrogen or carbon. Titanium silicon carbide (Ti3SiC2) is a MAX phase compound with a layered structure and is an encouraging candidate for high-temperature applications. It has hexagonal crystal structure, lattice parameters of c = 1.7669 nm and a = 0.3068 nm. In addition to ease of machinability, this material has excellent properties such as electrical and thermal conductivity of 4.5 × 106 Ω_1 m_1 and 40 W/mK, respectively, proper thermal shock resistance, high Young's modulus (320 GPa), high toughness (6–11 MPa m1/2), moderate flexural strength (260–600 MPa), and low hardness (~4 GPa). Therefore, Ti3SiC2 has great potential to be used in high-temperature applications (e.g., heating elements, metal smelting, and automobile engines) and is a suitable substitute for superalloys in many chemical and petrochemical applications. In recent years, some efforts have been made to develop Ti3SiC2-based composite ceramics. In this regard, hard secondary phases have been incorporated into the Ti3SiC2 matrix to improve the desired properties. It has been reported that the presence of SiC as a reinforcing phase improves the oxidation, thermal shock, and wear resistance of composites. However, a more indepth understanding of the mechanisms by which a secondary phase performs in a MAX phase matrix is still missing. The high-density Ti3SiC2-SiC composites with different SiC volume contents were fabricated by hot pressing technique under 35 MPa in a vacuum atmosphere at 1550 °C for 30 min. Microstructural observation showed that the distribution of SiC particulates in the Ti3SiC2 matrix was uniform which improved the hardness of Ti3SiC2–20 vol% SiC sample (13.9 GPa), compared to monolithic Ti3SiC2 (7.1 GPa). The sample containing 15 vol% SiC showed the highest flexural strength value, compared to the other Ti3SiC2-SiC samples and the monolithic Ti3SiC2. The fracture toughness of the Ti3SiC2-SiC samples was also lower than that of the monolithic Ti3SiC2 MAX phase.
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