先驱体法HfCSiB超高温陶瓷纤维的制备技术、组成结构调控与性能研究

Ultra-high-temperature ceramic materials with high-temperature resistance and high-temperature oxidation resistance are urgently needed in the aerospace technology field. However, the widespread hard-melting properties of ultra-high-temperature organometallic polymer precursors make the preparation of ultra-high-temperature ceramic fibers to become a difficult research problem. This project intends to adopt precursor derived method to prepare HfCSiB ceramic fiber on the basis of solving the synthetic problems of hafnium-containing main-chain polymer, poly(hafnium-silicon-carbon-boron). The ceramic fiber will be prepared via effective controlling of the melting characteristics of precursor through construction of segment length and chain structure, and subsequent melt spinning, crosslinking and inorganic conversion. The precursor synthesis, crosslinking and ceramization mechanism as well as high-temperature resistant mechanism will be revealed. Moreover, the effect of precursor composition and structure, crosslinking and pyrolysis process on the elemental composition and bonding state of the ceramic fiber will be established, which will thereby regulate the fiber performance. This project will carry out original works for the adjustment of the chemical composition and properties of HfCSiB fiber through precursor synthesis, melt spinning, crosslinking, pyrolysis and so on. In summary, this project can not only solve the preparation problem of ultra-high-temperature ceramic fiber, but also reveal the composition and structure evolution as well as the structure-performance relationship of hafnium-containing main-chain polymers and their derived ceramics. The success of this project can lay important foundation for the development of ultra-high-temperature ceramic fiber and their application in the aerospace field.

兼具耐超高温和高温抗氧化特性的超高温陶瓷材料在空天技术领域需求极为迫切。然而由于超高温有机金属聚合物先驱体普遍存在难熔融特性，使得如何制备出超高温陶瓷纤维成为该领域的研究难题。本项目拟采用先驱体法，在解决主链含铪的聚铪碳硅硼烷合成技术难题的基础上，通过对目标先驱体结构链段和链长的构建，实现对先驱体熔融特性的有效调控，进而通过熔融纺丝、交联及无机转化制备出HfCSiB陶瓷纤维,揭示先驱体合成、交联与无机化机理及耐超高温机制，确立先驱体组成与结构、交联与裂解工艺对纤维组成、键合状态的影响，从而调控其性能。本项目将在先驱体合成、熔融纺丝、交联、裂解等多种途径调节HfCSiB纤维的化学组成与性能等方面开展原创性工作。此项目的成功，不仅能突破超高温陶瓷纤维制备技术难题，而且将揭示主链含铪先驱体及其热解陶瓷的组成、结构演变规律及其构效关系，为超高温陶瓷纤维的研发及其在空天领域的应用奠定重要基础。

兼具耐超高温和高温抗氧化特性的超高温陶瓷纤维在空天技术领域需求极为迫切。先驱体转化法可以通过聚合物先驱体的分子设计，实现陶瓷材料成型和组成结构调控，是制备耐超高温陶瓷纤维最有效的技术途径之一。本项目掌握了主链含铪多元聚合物先驱体合成及其转化制备超高温陶瓷纤维的关键技术，揭示了主链含铪先驱体及其热解陶瓷的组成、结构演变规律及其构效关系，开发出兼具耐超高温和高温抗氧化特性的新型多元陶瓷纤维。本项目制备的超高温陶瓷先驱体与超高温陶瓷纤维可在高超声速飞行器鼻锥、前缘等热防护结构和燃烧室、喉衬等发动机构件上有很好的应用前景。