Method for Enhancing Transduction of Antisymmetric Lamb Waves

Antisymmetric Lamb waves are frequently used in nondestructive testing due to their high resolution and unique dispersive characteristics. However, they are less effectively excited by patch transducers compared with symmetric Lamb waves because of their antisymmetric deformation patterns. In this study, we propose a new method to enhance the transduction efficiency of antisymmetric Lamb waves using a new phenomenon of multimodal resonance. To generate the resonance, we attach an elaborately-designed resonating slab between a patch transducer and a target plate to be excited. To demonstrate the validity of our idea, both numerical and experimental results are presented.