Abstract The present study investigated preparation of the mullite/B4C composites through microwave and spark plasma sintering processes. A high-energy ball mill was used to mix the nono-sized mullite and B4C powders in ethanol media for 10 min. The mixed nano-sized powders were pelletized and sintered by microwave (MW) and spark plasma sintering (SPS) processes at 1500 and 1300 °C, respectively. The XRD results revealed the reactions between mullite and B4C, and also the formation of SiC, Al2O3, Si phases in SPS sintered sample. The identified crystalline phases in the microwave sintered sample were mullite and B4C. Samples sintered in SPS reached almost full density and showed improved mechanical properties (the hardness of 16.29 ± 0.2 GPa, bending strength of 348 ± 21 MPa and fracture toughness of 3.01 ± 0.18 MPa m−1/2) than those sintered in microwave. The microstructural investigations showed the formation of needle-like mullite at some areas of sample sintered in SPS with a uniform distribution of B4C in mullite matrix alongside pore-free microstructure. The microstructure of microwave sintered sample contained a large number of pores.

中文翻译：

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莫来石/B 4 C复合材料的制备：加热方法影响的比较研究

摘要 本研究研究了通过微波和放电等离子烧结工艺制备莫来石/B4C 复合材料。使用高能球磨机将非粒径莫来石和 B4C 粉末在乙醇介质中混合 10 分钟。混合纳米级粉末分别通过微波 (MW) 和放电等离子体烧结 (SPS) 工艺在 1500 和 1300 °C 下造粒和烧结。XRD 结果揭示了莫来石和 B4C 之间的反应，以及 SPS 烧结样品中 SiC、Al2O3、Si 相的形成。微波烧结样品中确定的结晶相是莫来石和 B4C。在 SPS 中烧结的样品几乎达到全密度并显示出改善的机械性能（硬度为 16.29 ± 0.2 GPa，弯曲强度为 348 ± 21 MPa，断裂韧性为 3.01 ± 0。18 MPa m-1/2) 比那些在微波中烧结的。微观结构研究表明，在 SPS 中烧结的样品的某些区域形成了针状莫来石，B4C 在莫来石基体中均匀分布，同时无孔微观结构。微波烧结样品的微观结构含有大量孔隙。