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SiC fiber-bonded ceramics (FBCs), as a new thermal-structural material obtained by hot-pressing sintering of SiC fiber, has low porosity, high fiber volume fraction, high temperature resistance, oxidation resistance and high strength. It is an excellent candidate material for high temperature components such as turbine blades and rotors of aero-engine. The research progresses of FBCs were systematically reviewed in this paper. The structural characteristics and preparation methods of two types of FBCs (Tyranohex and SA Tyranohex) were introduced, the relationships among the composition, structure and performance of FBCs were discussed. It was noted that the interface carbon layer plays a crucial role in the performance of FBCs. The mechanical properties of SA-Tyranohex at room temperature and high temperature were highlighted, and the reasons for its excellent high temperature performance were analysed. The examination, verification and application development were summarized. The difficulties of FBCs in forming complex components were pointed out, and the future development trends and research directions were prospected. Finally, it was proposed that conducting research on SiC fiber-bonded ceramics is of great significance for the development of new materials for high-temperature resistant components in China.

A strong and tough Ta/TaHfC2‐laminated composite was proposed and investigated in terms of its thermoablative behavior under plasma flame for a medium–long time (30–120 s) beyond 2517 K. In comparison to TaHfC2, the composite performed a better thermal shock resistance but an equivalent linear ablation rate (−5.40 vs. −4.08 μm/s) after ablation for 30 s. With extending the ablation time, the linear ablation rate of the composite increases. Combined with the characterization results of the ablative layer and the established volatile phase diagram at 2273 K, it was found that the composite mainly undergoes active oxidation, passive oxidation, and dissolution of oxygen during the ablation, whereas its ablative layer mainly experiences the sintering, solid solution, and loss processes of oxides. The reason the composite possesses a good ablation resistance is because the introduction of Ta‐foil‐improved toughness as well as protective effect of the ablative layer of TaHfC2. [ABSTRACT FROM AUTHOR]

Ta‐Hf‐C ternary ceramics are good candidates for structural components used in extreme thermal environment. However, intrinsic brittleness greatly restricts their applications in reality. Here, we report a novel TaHfC2‐based composite with superior strength and toughness by employing Ta foil as interlayers to generate a multi‐scale laminated structure together with the in situ formed Ta2C MXene during sintering. Owing to the unique composition and microstructure, the tensile strength, shear strength, fracture toughness (KIC), and work of fracture of Ta/TaHfC2 have reached 233 ± 12 MPa, 64 ± 6 MPa, 13.16 ± 0.03 MPa·m1/2, and 1726 ± 448 J/m2 simultaneously, and all showed substantial increments when compared with TaHfC2 monolithic ceramic and related Ta‐Hf‐C materials as showed in literatures. This study significantly improved the toughness of TaHfC2, and it provides a new high‐performance thermal structural material for the aerospace industry as well as a new idea for toughening ultra‐high temperature ceramics (UHTCs) of transition metal carbides. [ABSTRACT FROM AUTHOR]