Abstract The impact of Si3N4 and SiC additives incorporation in the microstructure and sintering behavior of TiB2-based composites were studied. Three ceramic composites including TiB2–Si3N4, TiB2–SiC, and TiB2–SiC–Si3N4 were manufactured by spark plasma sintering (SPS) at 1950 °C for 8 min under 35 MPa. The acquired ceramics were analyzed by X-ray diffractometry and scanning electron microscopy. In addition, the sintering thermodynamic was investigated using the HSC Chemistry package. X-ray diffraction patterns of the prepared ceramics revealed the in-situ formation of graphite and boron nitride in the final composites initiated from SiC and Si3N4, respectively. The thermodynamic assessments proved the role of liquid phase sintering on the sinterability enhancement of all composite samples. Field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy verified the in-situ formation of both BN and graphite components in the sample containing SiC and Si3N4 additives. Finally, the fractographical investigations clarified the transgranular breakage as the main fracture mode in the TiB2-based ceramics.

中文翻译：

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离散和同时添加 SiC 和 Si3N4 对 TiB2 陶瓷显微组织发展的影响

摘要 研究了Si3N4 和SiC 添加剂对TiB2 基复合材料微观结构和烧结行为的影响。三种陶瓷复合材料，包括 TiB2-Si3N4、TiB2-SiC 和 TiB2-SiC-Si3N4，是通过放电等离子烧结 (SPS) 在 1950 °C 下在 35 MPa 下进行 8 分钟制造的。通过X射线衍射和扫描电子显微镜分析获得的陶瓷。此外，使用 HSC Chemistry 软件包研究了烧结热力学。制备的陶瓷的 X 射线衍射图显示石墨和氮化硼在分别由 SiC 和 Si3N4 引发的最终复合材料中原位形成。热力学评估证明了液相烧结对所有复合样品的可烧结性增强的作用。场发射扫描电子显微镜和能量色散 X 射线光谱证实了含有 SiC 和 Si3N4 添加剂的样品中 BN 和石墨组分的原位形成。最后，断口研究阐明了穿晶断裂是 TiB2 基陶瓷的主要断裂模式。