Analysis of acousto-ultrasonic characteristics for an isotropic thin plate

For the purpose of understanding and improving the acousto-ultrasonic (AU) technique, the AU characteristics for an isotropic plate is investigated in this paper. Unlike the previous wave tracing method, a spectral analysis approach is presented, which can take into account the effects of the transducers’ characteristics. Using this approach and introducing the point source/point receiver assumption, the input–output frequency spectrum relationships for the cases of one transmitter/one receiver and one transmitter/multiple receivers coupled to an isotropic thin plate are expressed in explicit forms. Based on this, a wave scattering parameter to bridge two different sensing types of the receiving transducers is presented, and a new type stress wave parameter for the AU technique is developed, which eliminates the influence of the complex mechanic-electron transduction characteristics of the receivers and also separates to some extent the effects of some other external factors such as transducer masses and locations. Finally, some numerical simulations are carried out and conclusions drawn concerning the AU technique.