Probabilistic damage imaging of composite plates by air coupled Lamb waves

Lamb wave of air coupled ultrasound can quickly detect the area of composite laminates. For the impact damage of quasi-isotropic carbon fiber composite laminates, a probabilistic damage imaging method independent of velocity is presented. Firstly, air-coupled ultrasonic transducers are used to scan in two orthogonal directions to obtain energy damage factors at different positions. Based on the probabilistic damage theory, the pixel points of each path are damaged probabilistically to determine the damage index of all paths. Finally, the damage indexes in each scanning direction are fused and the threshold value is introduced to realize the imaging of impact damage. The experimental results show that the damage factor combined with probabilistic damage imaging can better realize the localization and reconstruction of impact damage, and the imaging accuracy can be further improved by introducing the threshold value.