Selection of piezoelectric material for double parabolic reflectors wave-guided ultrasonic transducers

抄録

To fit double parabolic reflectors wave-guided ultrasonic transducer (DPLUS) for high-power ultrasound applications, in this study, we investigate the selection criteria of piezoelectric material. Five types of piezoelectric material were compared to improve the mechanical output of DPLUS: three types of lead-zirconate-titanate (PZT) and two types of lead-free piezoelectric material. Analytical modelling, numerical simulation, experiments were combined, and two working conditions were examined. At non-resonant excitation of DPLUS waveguide, d33 of piezoelectric material was found to be a reliable evaluation index. PZT types DPLUS with large d33 are promising for this case. At resonant excitation of DPLUS waveguide, two circumstances should be distinguished. For low-frequency modes excitation, the excitation of modes guided by the matching issue are more essential than piezoelectric material properties. In contrast, for high-frequency modes excitation, properties of piezoelectric material especially permittivity are the key to improve the output performance of DPLUS, and lead-free types were found to be effective. There conclusions are significantly important to improve the performances of DPLUS for various potential applications.