Modeling Magnetostrictive Transducers for SH Guided Wave Generation and Reception for Structural Health Monitoring

Shear horizontal (SH) guided waves are great options for nondestructive testing and structural health monitoring (SHM) applications in plates due to their simple dispersion behavior and long-range inspection capability. Being shear waves, they do not leak into fluid that may be present on the plate surface. Magnetostrictive transducers (MSTs) are relatively simple, cost-effective transducers that can generate and receive SH guided waves. However, modelling of the transducer functionality has been quite limited to date. Therefore, in this study, finite element modeling using the COMSOL Multiphysics software was performed to better understand the effect of transducer design variables and transducer layout on SH guided wave-based SHM. We investigated the effect that the thickness of the adhesive and meander coil liftoff have on MST generation characteristics. Additionally, the benefit of two-sided transducers relative to single-sided transducers for symmetric and antisymmetric wave modes was clarified. The results provide suggestions for MST design optimization and further improvement of its capability for SHM and NDE.