SiC_p/MoSi_2原位反应高温热压复合工艺的研究

In-situ Reaction and Hot Press Synthesis of SiC_p/MoSi_2

运用乙醇湿法混合和氩气保护原位反应高温热压方法制备了不同配比的SiCp/MoSi2复合材料,研究了原位生成的SiC颗粒对MoSi2基体材料显微结构和室温力学性能的影响。结果表明:原位反应高温热压制备SiCp/MoSi2的工艺是可行的,反应生成的适量SiC颗粒细化了基体晶粒,改善了其力学性能;与该工艺下制备的纯MoSi2相比,含40vol%SiCp的SiCp/MoSi2复合材料室温抗弯强度提高了260%,含50vol%SiCp的SiCp/MoSi2复合材料室温断裂韧性提高了50%;该种工艺的强化机制为细晶强化和弥散强化,韧化机制为细晶韧化。

SiCp/MoSi2 composites with different volume fraction of SiC particles were prepared by the technology of in-situ reaction and hot press synthesis in argon atmosphere after alcohol wet mixing. The effects of in-situ SiC particles on microstructure, fracture surface and room mechanical properties of the composites were studied. The research shows that SiCp/MoSi2 composites can be fabricated by in-situ reaction and hot pressing. SiC particles decrease the grain size of MoSi2 matrix and improve its mechanical properties. Compared with the mono materials, the bending strength of the composites with 40vol% SiC, increases 260%. and the fracture toughness of the composites reinforced with 50vol% SiCp increases 50%. The strengthening mechanism of the composites is of fine grain and dispersion strengthening. while the toughening mechanism is of fine grain toughening.