SiC纤维束界面层连续化学气相沉积设备研制

Development of CVD Equipment for Continuous Coating of Interface Layer on SiC Fiber

SiC纤维增强SiC陶瓷基复合材料具有低密度、耐高温、高强韧性的优异性能,是新型航空发动机热端部件的理想结构材料。界面层决定了SiCf/SiC复合材料增韧效果等关键性能,其制备对于复合材料工程化应用至关重要。我国在SiC纤维束界面层制备的研究应用方面明显滞后,存在的主要问题之一是缺乏可连续化学气相沉积制备均匀、一致、质量稳定的界面层的设备。针对该问题,设计了可在SiC纤维束基体上连续沉积界面层的设备;通过纤维运送机构实现了SiC纤维束的连续运送,且速度、张力可控,同时对设备的低压密封系统提出了气氛分隔设计,实现了将反应气氛约束在反应区内的目的,并通过模拟仿真进行了验证。

SiC fiber reinforced SiC ceramic matrix composite has excellent properties of low density,high temperature resistance,high strength and toughness,which makes it an ideal structural material for hot end parts of advanced aeroengines.The key performances of SiCf/SiC composite,such as toughening effect,are determined by interface layer.And the preparation of it is crucial for the engineering application of composite materials.The research and application of interface layer preparation for SiC fiber in China lags behind obviously.One of the main obstacles lies in the lack of equipment for continuous chemical vapor deposition to uniformly,consistently and stably prepare interface layers.Focusing on this problem,a CVD equipment to continuously deposit interface layer on SiC fiber substrate is designed.The continuous transport of fiber substrate is realized by a fiber transporting mechanism with controllable speed and tension.Simultaneously,an atmosphere separation design of the low-press sealing system is applied and the purpose of isolating the reaction atmosphere in the reaction zone is realized.The effect of this design is verified and evaluated by simulation.