电场辅助短切碳纤维织构化强韧(Ta,Hf)C-SiC复相陶瓷的3D打印及其服役行为的跨尺度表征

由于航空发动机热端部件对高温力学性能、成型工艺和可靠性等核心问题提出了更高的要求，本项目拟通过基于光固化成型的3D打印方法制备具有单层织构化和整体螺旋结构的碳纤维增强(Ta,Hf)C-SiC复相陶瓷，并对该体系的高温抗蠕变等服役行为进行跨尺度表征，寻求解决航空发动机复相陶瓷的相关核心基础科学问题并提出具体方案。具体通过表面接枝改性实现高折射率碳化物复相陶瓷材料的光固化3D打印，通过引入电场辅助及旋转料槽的手段实现短切碳纤维的单层织构化从而形成整体螺旋结构达到对复相陶瓷强韧化的目的，通过调整不同元素的体积效应和热膨胀系数的差异以及这两个因素的协同机制而实现高温烧结环境中的裂纹自愈合，通过对模拟工况下高温服役行为进行跨尺度表征构建陶瓷材料组织结构-陶瓷材料力学性能与陶瓷材料抗蠕变性能的关系模型。最终实现面向航空发动机的超高温复合陶瓷材料的基础科学问题的深入研究并拓展其应用。

Due to the higher requirements for high temperature mechanical properties, forming technology and reliability of hot-end components of aero-engine, this project intends to prepare carbon fiber reinforced (Ta, Hf) C-SiC multiphase ceramics with single-layer texture and integral helical structure by 3D printing method based on stereolithography, and to conduct multi-scale characterization on the service behavior such as high temperature creep resistance. We will research into the key basic scientific problems of high temperature ceramic composites used in aero-engine and seek for the corresponding solutions. 3D printing of carbide composite ceramics with high refractive index would be realized by surface grafting modification. Single-layer texture of short carbon fibers would be realized by introducing the approach of electric field assistance and rotating tank, to form a whole helical structure to strengthen and toughen the composite ceramics. The self-healing of cracks at high temperature sintering environment would be realized by the synergistic mechanism of volume effect and difference of thermal expansion coefficient of different elements. The relationship model between the microstructure of ceramic materials, mechanical properties and creep resistance of ceramic materials will be constructed by multi-scale characterization of high temperature service behaviors under simulated working conditions. Ultimately, the fundamental scientific problems of ultra-high temperature composite ceramics for aero-engine will be deeply studied and their applications will be expanded.