氮气催化辅助燃烧合成法制备纳米β-SiC粉体性能及机理研究

High-performance new materials are the key security to the social development and promote the national economy. Accelerating the development of the high- performance new material industry is the urgent need to build the manufacturing power. The β-SiC ceramic material with good mechanical, thermal, high temperature oxidation resistance and other performances has become an indispensable key material, which performances depend largely on the quality of nano β-SiC powder used. In view of the problems of traditional method to prepare nano β-SiC powder including high content of impurities, complicated process, not achieving mass production, this project proposes the new process of catalysts assistant of nitrogen gas combustion syntheses, using high purity nitrogen gas to catalyze and assist the Si - C weak exothermic system to attain the efficient reaction; preparing the nano β-SiC powder with high purity, narrow distribution of particle size, equiaxial shape, high sintering activity; building the corresponding relationship between the preparation process of the nano β-SiC powder and the performance of the product; clarifying Si - C - N2 system evolution law in the combustion synthesis process; summarizing the synthesis mechanism and growth rule of the nano β-SiC powder; building the nano β-SiC powder’s growth model; forming the theoretical system of the controllable preparation of the nano β-SiC powder.. This project is expected to play a huge role in promoting industrial development of high-performance new materials, having important academic value and broad market application’s prospect.

高性能新材料是社会发展和提升国民经济的关键保障，加快高性能新材料产业发展是建设制造强国的迫切需求。β-SiC陶瓷材料以其良好的力学、热学、高温抗氧化等性能成为了不可缺少的关键材料，而其性能很大程度上取决于烧结所用的纳米β-SiC粉体的质量。针对传统方法制备的β-SiC粉体存在杂质含量高、工艺繁琐、无法规模化生产等问题，本项目提出氮气催化辅助燃烧合成的新型工艺，利用高纯氮气催化辅助Si-C弱放热体系发生高效反应，制备得到高纯度、粒度分布窄、等轴状、高烧结活性的纳米β-SiC粉体，建立制备纳米β-SiC粉体的工艺与产品性能的对应关系，阐明Si-C-N2体系在燃烧合成过程中的演变规律，总结纳米β-SiC粉体合成机制与生长规律，构建纳米β-SiC粉体生长模型，形成纳米β-SiC粉体可控制备的理论体系。.本项目研究有望对高性能新材料产业发展起到巨大的推动作用，具有重要的学术价值和广阔的市场应用前景。