Feasibility of ultrasonic guided waves for detecting surface-breaking cracks in laminated composite plate structures
Ultrasonic guided waves are attractive for rapid inspection of laminated composite structures, where the cracks developed transverse to the loading direction are the serious type of damage. In this context, the paper presents studies of guided wave interaction with transverse cracks in symmetric and non-symmetric cross-ply composite laminates. In view of this, a two-dimensional finite element approach is used to gain physical insight into the reflection regime. Reflection ratios for GFRP/CFRP cross-ply laminates with various surface-breaking/transverse crack sizes are calculated, and results are presented in frequency spectrum, which shows that the minimum crack depth of 0.0093 of the operating wavelength has been successfully detected. Effect of different ply layup orientations is also considered. This work will be useful for practical guided wave-based inspection of composite plate structures.