Ultrasonic Guided Waves Scattering Effects From Defects in Adhesively Bonded Lap Joints Using Pitch and Catch and Pulse-Echo Techniques

摘要

In this article a method to evaluate defect dimensions in adhesively bonded lap joints based on the measurement of scattering effects of ultrasonic guided waves is presented.A simplified theoretical model is proposed which was initially tested in plates with through holes.The experimental results obtained using both pitch-and-catch and pulse-echo techniques for 500 kHz and 1MHz frequencies confirm the validity of this model.To evaluate the lap joint defects,a set of samples with artificial defects were manufactured and the form and dimensions were confirmed using C-scan ultrasonic images.With the same methodology used in through-hole analysis,scattering effects of defects were measured.The results obtained with the pitch-and-catch technique with 1MHz transducers allow us to say that an estimate of defect dimensions could be done by using the proposed model with reasonable accuracy and according with the predictions.