SiC/MoSi_2复合材料的原位反应热压烧结工艺

In-situ reaction hot-pressing sintering process of SiC/MoSi_2 composites

从热力学角度研究了Mo-Si-C三元系中所有二元化合物化合反应的吉布斯自由能随温度变化的规律,探索了SiC/MoSi2复合材料原位反应热压烧结的最佳工艺参数。结果表明,利用Mo、Si、C混合粉末原位反应合成SiC/MoSi2复合材料在热力学上是完全可行的,反应烧结温度低于1728K(1455℃)是为抑制Mo2C形成,保证SiC生成的热力学条件。采用原位反应热压烧结工艺能够制备具有优异显微组织的SiC/MoSi2复合材料。

The Gibbs free energy change rule of binary compound in Mo-Si-C system vs temperature was studied from the view of thermodynamics, and the optimum technological parameters of in-situ reaction hot-pressing sintering of SiC/MoSi2 composites were proposed. The results show that it is feasible to synthesize SiC/MoSi2composites with in-situ reaction by using Mo, Si and C mixture powder in thermodynamic field. The reactive sintering temperature lower than 1728 K（ 1455 ℃ ）is the thermodynamic condition to inhibit Mo2C formation and guarantee SiC formation. SiC/MoSi2 composites with excellent microstructure can be prepared by adopting in-situ reaction hot-pressing process.