连续碳化硅长丝纤维生产技术现状

Current Technologic State of Continuous Silicon Carbide Filament

连续碳化硅长丝纤维是目前具有最高比强度和最高比模量,以及高热稳定性的人造纤维。其生产技术发展经历了从高含氧量到超低含氧量,从微量元素掺杂到多种元素掺杂复合连续碳化硅长丝纤维几个关键技术阶段。连续碳化硅长丝纤维生产的4个关键技术工艺过程包括:有机硅烷小分子单体经化学或催化聚合形成有机聚硅烷(Polysilanes,PS)的聚合过程;PS的粘溶液或熔浆在惰性气氛中机械纺丝制造PS原丝的工艺过程;PS原丝经过在惰性化学气氛中控温化学转化形成聚碳硅烷(Polycarbosilanes,PCS)纤维及同时发生交联的热化学转化过程;PCS纤维在惰性以及/或者反应性气氛中高温热交联结晶化形成终烧碳化硅纤维的高温热化学转化过程。熟悉并完全掌握每一个工艺过程的技术关键,才能有效选择合适的工艺及生产装备,生产出高强度高模量连续碳化硅长丝纤维,为我国航空航天以及高端制造业提供高品质连续碳化硅长丝纤维材料。

Continuous silicon carbide filament is, up to date, an artificial fiber that has the highest tensile strength and the highest tensile modulus, as well as very high thermostability. Its production technology experienced several key stages, from high oxygen content to ultra-low oxygen content, and from trace element composites to multiple elements composites. There are four key processes of continuous silicon carbide （SiC） filament production technology mainly. These are ： the chemical or catalytic process that converts organosilane monomer into organo-polysilane （PS） ; the process of converting a viscous PS solution or molten PS into long and dry fibers, i.e. filament fabrication ; the process that converts the original PS filament into polycarbosialne （PCS） in an inert and/or chemical vapor environment under controlled temperatures; and finally the high temperature thermochemical cross-linking process of converting the PCS filament into highly crystalline SiC filament in an inert and/or chemical vapor environment under high temperature conditions. It is obvious that only if one is completely familiar with and rigorously grasp these key processes, one would be able to effectively select a suitable technical process, to choose or create suitable manufacturing facilities, and therefore to be able to produce high strength and high modulus continuous silicon carbide filament. And then one would be able to provide high quality source of continuous silicon carbide filaments for the nation＇ s aero and space, as well as high performance manufacturing industries.