碳纳米管（CNTs）具有极高强度和韧性，被誉为最理想的纳米增韧材料和纤维类强化相的终极形式。但目前CNTs增强陶瓷复合材料存在CNTs不易分散，体积分数低和界面结合差的缺点，较少有力学性能大幅提高的报道。本项目创新地提出化学气相沉积（CVD）法温度低、界面可控和不损伤CNTs等优点跨尺度制备高体积分数CNTs/SiC。按CNTs取向适当排列、铺层和编织，CVD原位沉积SiC获得纳米级、微米级和毫米级多维复合材料，可形成尺度小、面积大、分布广、结合强的界面，表现出增强体细化和基体细化协同强韧化的新模式。研究界面小尺度新特性与大尺度宏观性能（强度韧性等）的映射关系，逐维建模计算与理论分析，揭示CNTs庞大纳米表面效应向复合材料界面效应的转变机理，材料维数变化与尺度变化的性能复合规律，以及纳米尺度下新的界面应力传递规律与韧化特性。丰富超轻高强纳米纤维增强陶瓷基复合材料制备方法和强韧化理论。

Carbon nanotubes (CNTs) with outstanding strength and toughness are optimal nanometer material for ultimate form of fibrous reinforcement. Until now, there are few articles published reporting that the mechanical properties of CNTs reinforced ceramic matrix composites (CMCs) have been greatly improved, because the CNTs reinforced CMCs have many challenges, such as poor dispersion quality, low volume fraction and bad interfacial bonding, to be overcome. In our project, chemical vapor deposition (CVD) method at low temperature is proposed to prepare CNTs/SiC composites on multi-scales with controlled interfaces, high CNTs volume fraction and free damage of CNTs. 1D, 2D and 3D preforms will be prepared with proper orientations, layers and laminations of the aligned CNTs, in which the SiC is then in-situ deposited by CVD to produce nano-, micron-, and millimetric-composites with interfaces of small nano-scale, large suface area, wide distribution and high bonding strength. New strengthening and toughening mode of the CNTs/SiC composites were obtained by reinforcement refinement and matrix refinement. Studying new characteristic of the nano-scale interfaces and its effect on macro-mechanical properties of these composites, building the calculational model and theoretically analyzing the experimental data on each dimension will reveal the transformation mechanism of huge nanometer surface effects of the CNTs to interface effects of the composites, composite rule of the material properties with change in scales and dimensions, and new nano-scale interfacial stress transfer law and toughening characteristic. This study will enrich the fabrication method and the strengthening-toughening theory of CMCs reinforced by nanofibres with very low density and ultra high strength properties.