人造陶瓷纤维的研究进展

Research progress of man-made ceramic fiber

陶瓷纤维作为新型的高温抗氧化、耐腐蚀纤维,被广泛应用于高温隔热材料。介绍了氧化铝纤维、莫来石纤维、氮化硅纤维、氮化硼纤维、碳化硅纤维、硼化锆纤维等陶瓷纤维的理化性能与制备方法,并详细综述了国内外陶瓷纤维的研究现状、技术难点。氧化铝纤维、莫来石纤维主要采用溶胶-凝胶法制备,但烧结过程中,晶粒尺寸、晶相转变温度和时间的控制是难点。氮化硅纤维主要采用聚碳硅烷氮化法制备,但制备的纤维炭含量偏高,影响透波性,优化先驱体、改进生产工艺有助于解决这一问题。有机先驱体法制备氮化硼纤维工艺条件苛刻、难控制,且对环境造成污染,找到污染小的先驱体原料的代替品,并优化制备工艺和条件是研究的重点。活性炭纤维转化法制备碳化硅纤维有明显的优势,但制备的纤维质量差,优化活性炭纤维的性能、活性炭纤维转化为碳化硅纤维的过程条件是下一步的研究方向。硼化锆纤维抗热震性差,与其他物质复合或共混可以增强硼化锆纤维的抗热震性。

Ceramic fiber as a new type of high temperature resistant,antioxidant and corrosion resistant fiber,is widely used as high temperature insulation materials.The physical and chemical properties and preparation methods of ceramic fibers,such as alumina fiber,mullite fiber,silicon nitride fiber,boron nitride fiber,silicon carbide fiber and zirconium boride fiber,were introduced.The research status and technical difficulties of ceramic fibers were reviewed in detail at home and abroad.Alumina fibers and mullite fibers are mainly prepared by sol-gel process,but the grain size and crystalline phase transition temperature and time is difficult to be controlled during sintering.Silicon nitride fiber is mainly prepared by polycarbosilane nitridation,but the obtained fiber has high carbon content,which impacts the wave permeability.The solution of this problem can be beneficial from optimizing the precursor and improving the production process.The preparation of boron nitride fiber by organic precursor method not only requires harsh process conditions difficult to be controlled,but also pollutes the environment.The research is to be focused on finding less polluted precursor raw materials as substitutes and optimizing the preparation process and conditions.The preparation of silicon carbide fiber by activated carbon fiber conversion method has obvious advantages,but produces poor fiber quality,so the further research is to optimize the properties of activated carbon fiber and the process conditions for the conversion of activated carbon fiber into silicon carbide fiber.Zirconium boride fiber has poor thermal shock resistance,which can be enhanced by compounding or blending with other substances.