Ultrasonic Edge Waves For Damage Detection In Composite Plate Stiffeners

A new inspection system has been created to detect damage on the edge of thin composite structures using ultrasonic waves localised at the plate edge. This has a wide range of potential applications, including composite wing panel stiffeners. Dispersion curves for edge and Lamb waves were generated numerically and verified experimentally. Damage detection was demonstrated using two experimental configurations: pitch-catch and pulse-echo. Measurements were performed with the use of tuned piezoceramic transducers attached to the plate edge at appropriate locations and baseline subtraction was used to detect damage on the edge of the plate. It was shown that impact damage could be detected and located using these methods on a carbon-fibre-reinforced polymer plate.