Abstract In this study, B6.5C-TiB2-SiC-BN composite was fabricated via reactive hot pressing from a powder mixture of TiCN, B, and Si. The reaction process of the powder mixture was investigated by heat treatment at elevated temperatures. The as-reacted powder products possessed a core-shell structure of TiB2 surrounded by h-BN. During densification, the h-BN in this structure acts as a diffusion channel and lubricant, which promoted the densification process. The extremely small size, fresh surface of in-situ formed phases, and uniform dispersion in synthesized powders also contributed to sintering. The designed reactive hot-pressing sintering effectively resolves the difficulty of obtaining uniformly-dispersed BN. The obtained bulk B6.5C-TiB2-SiC-BN composite ceramic shows high relative density (98.8%) and good comprehensive mechanical properties including hardness, bending strength, and fracture toughness of 19.6 GPa, 801 MPa, and 5.31 MPa m1/2, respectively.

中文翻译：

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TiCN-B-Si混合物反应热压制备精细高性能B6.5C-TiB2-SiC-BN复合材料

摘要 在这项研究中，B6.5C-TiB2-SiC-BN 复合材料是由 TiCN、B 和 Si 的粉末混合物通过反应热压制成的。通过高温热处理研究粉末混合物的反应过程。反应后的粉末产物具有被 h-BN 包围的 TiB2 核壳结构。在致密化过程中，该结构中的 h-BN 作为扩散通道和润滑剂，促进了致密化过程。原位形成相的极小尺寸、新鲜表面以及在合成粉末中的均匀分散也有助于烧结。设计的反应热压烧结有效地解决了获得均匀分散的BN的困难。获得的块状 B6.5C-TiB2-SiC-BN 复合陶瓷显示出较高的相对密度 (98.