In this work, 3D-C_f/HfC-SiC-based composites were fabricated and optimized via reactive melt infiltration (RMI) of Si into porous C_f/HfC-C preforms prepared by a sol-gel processing. The physical and chemical processes involved during the fabrication were identified and analyzed in details. It is revealed that fibers and interphase of the composites can be eroded during carbothermal reduction process, which can be further aggravated during RMI, with the formation of Hf-containing substance on the fibers surface. The fibers and interphase degradation is mainly induced by the reactions between HfO₂ and C/SiC interphase layers at elevated temperatures. Accordingly, a two-step carbothermal reduction treatment was proposed for the optimization of the fabrication procedure. As a result, less fiber/interphase erosion and improved mechanical properties are achieved in the composites, with the bending strength increased by ∼49 % (from 214.1 ± 15.7 MPa to 319.0 ± 26.0 MPa).

在这项工作中，通过将硅反应熔融渗入（RMI）到通过溶胶凝胶工艺制备的多孔C _f / HfC-C预成型坯中，对3D-C _f / HfC-SiC基复合材料进行了制造和优化。确定并详细分析了制造过程中涉及的物理和化学过程。结果表明，复合材料的纤维和中间相在碳热还原过程中会被侵蚀，在RMI过程中会进一步加剧，并在纤维表面形成含H的物质。纤维和相间降解主要是由HfO ₂之间的反应引起的和C / SiC相间层在高温下。因此，提出了两步碳热还原处理以优化制造工艺。结果，在复合物中获得了更少的纤维/相间腐蚀，并改善了机械性能，弯曲强度提高了约49％（从214.1±15.7 MPa增加到319.0±26.0 MPa）。