Microacoustic Imaging Technique for Bulk Microstructure Characterization of Woven CFRC Materials
In short wavelength case ultrasound propagation through woven carbon fiber-rein-forced composite (CFRC) materials essentially depends on their microstructure.Fiber bundle and weaving ply can be considered as basic structural elements of woven CFRC laminates.These structural units provide effective reflectors when ultra-short impulse high frequency ultrasound impinges on woven laminates.The reflection coefficient R0 achieves level of 3%-15% at ply-ply interface,0.2-0.4 in resin pocket region.This magnitude of reflection coefficient offers reasonable acoustic contrast to see packing,lay-up and resin pockets in woven laminate body by acoustic imaging methods.Microacoustic imaging technique is based on time-resolved echoes from reflections in woven CFRC laminates.A focal system with low aperture angle is used to generate 20-40 probe ultrasonic pulse wave.Its spatial resolution is up to 60mm at 50MHz in woven CFRC laminate.The results presented in this paper demonstrates the possibility and potentiality of characterization of microstrueture of woven CFRC laminates.Packing,lay-up,weaving nature,fiber bundle,resin pocket as well as their topology are exhibited clearly in the acoustic images by using microaeoustic technique.
作 者： Liu Songping Guo Enming Liu Feifei Li Legang V.M.Levin Yu S Petronyuk 作者单位： Liu Songping,Guo Enming,Liu Feifei,Li Legang(Beijing Aeronautical Manufacturing Technnology,Research Institute)V.M.Levin,Yu S Petronyuk(Lab of Acoustic Microscopy,Institute of Biochemical Physics,Russian Academy of Sciences)
刊 名： 航空制造技术 ISTIC 英文刊名： AERONAUTICAL MANUFACTURING TECHNOLOGY 年，卷(期)： 2007 ""(z1) 分类号： V2 关键词： Ultrasonics Woven composites Microstructure Acoustic imaging