Fiber reinforced polymers (FRP) materials are widely used in many industries including aerospace, automotive, marine, and construction. Numerous nondestructive evaluation (NDE) techniques have been used to assess the condition of FRP coupons. However, the complex geometries and irregular shapes of FRP components in actual
applications limit the applicability of NDE for in-service monitoring. In this paper, acoustic emission (AE)
monitoring was implemented for damage evaluation in a realistic carbon fiber reinforced polymers (CFRP) specimen. The specimen had irregular shape and thickness. Stepwise loading was applied to the specimen and an AE based numerical condition assessment criteria for real-time monitoring was used to evaluate the damage. Ballistic
impact test was also conducted to assess the ability of AE in locating the damage. AE data filters were developed to reject signals from noise and wave reflections. The methodology used to detect, evaluate and locate damage using AE is reported. Preliminary results for CFRP damage classification (matrix cracking, fiber breakage, and delamination) based on AE data are also presented.
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