氧化锆连续晶体纤维的结构转变与单晶化控制及其复合连续晶体纤维研究

Zirconia (ZrO2) continuous crystal fiber was a more advanced thermal-resistant and composite material. The key preparation technology of the continuous ZrO2 crystal fibers was patented by our group using polyorganozirconium as the precursors, and the ZrO2 continuous fibers have been obtained with the largest tensile strength of 2.8GPa. But some scientific problems of the fibers were appeared under high-temperatures, such as high temperature creep, abnormal growth of the grains, brittle failure and so on. In order to enhance the single crystallization and optimize high temperature properties of the ZrO2 continuous fibers, we intend to control the ordering and the structure transformation process of the precursors in the view of coordination chemistry and crystallography with the help of high temperature team pressure technology. For preventing grain boundary sliding, grain boundary phases were introduced combined with rapid ultra-temperature and two-steps calcinations process. Uniform infrared reflection coatings were formed on the surface of the fibers by solvothermal and in situ growth method, which was to reduce the thermal radiation of the high temperature and driving force of grain growth and restrain the abnormal growth of the grains. Another, ZrO2-based composite continuous crystal fibers were carried out on the basis of ZrO2 continuous crystal fibers, and the relative thermal, mechanical and catalytic properties of the fibers were researched. These studies have very important values on the academic and economic fileds, and provide updated and higher development platform for other structural, functional and composite fibers.

氧化锆连续晶体纤维是一种更先进的隔热和复合增强材料，本课题组采用聚锆前驱体法已解决其关键制备技术，并授权多项发明专利，获得了连续可纺、最大强度达2.8GPa的连续纤维。在此基础上，针对纤维高温下存在高温蠕变、晶粒异常长大、易脆断等问题，从配位化学和结晶学的角度，严格控制前驱体的有序性和结构转变过程，借助高温蒸汽压力解析技术，提高纤维单晶化程度，优化高温性能。通过引入晶界相并结合快速超高温-两步烧结工艺，阻止晶界滑移；利用溶剂热和原位生长方法，在纤维表面形成均匀高温红外反射层，减少高温对纤维的热辐射，降低晶粒生长驱动力，抑制晶粒异常长大。再者，以氧化锆连续纤维为载体，开展复合连续晶体纤维的探索工作，并研究其热学、力学、催化等性能。提高氧化锆连续晶体纤维单晶化程度、抑制晶粒异常长大等基础科学问题的解决，在学术和经济上都具有重要价值，也为其他结构、功能、复合纤维的研制提供更新、更高的发展平台。

氧化锆连续晶体纤维是一种更先进的隔热和复合增强材料，本课题组采用聚锆前驱体法已解决其关键制备技术， 并授权多项发明专利， 获得了连续可纺、 最大强度达 2.8GPa的连续纤维。本项目从配位化学和结晶学的角度，探明了前驱体的有序性和结构转变过程，借助高温蒸汽压力解析技术，研究了温度、浓度等可纺性溶胶的影响；通过对组成纤维晶粒的形貌的变化，提出了纳米晶基元生长的模型，获得了高度取向的氧化锆晶体纤维；利用前驱体溶胶-凝胶技术，发明了Y2O3和TiO2纤维的制备方法，结合氧化锆纤维隔热材料进行了近红外发射性能的测试表征。再者，以氧化锆连续纤维为载体，开展了CeO2-ZrO2-Y2O3、ZrO2-Y2O3等复合晶体纤维的探索制备工作，并研究其形成机理以及热学、力学等性能。提高氧化锆连续晶体纤维单晶化程度、抑制晶粒异常长大等基础科学问题的解决，在学术和经济上都具有重要价值，也为其他结构、功能、复合纤维的研制提供更新、更高的发展平台。