Design and Performance Optimization of a High-Frequency Broadband Transducer Based on P(VDF-TrFE)

To address the increasing demand for bandwidth expansion in hydroacoustic transducers, this study presents a high-frequency broadband transducer design that utilizes a novel piezoelectric material, poly(vinylidene fluoride-co-trifluoro ethylene)copolymer(P(VDF-TrFE)). The low mechanical quality factor of P(VDF-TrFE) effectively mitigates resonance effects and significantly enhances the bandwidth performance of the transducer. In this study, the effects of piezoelectric material thickness, lateral dimension, and double-layer nonuniform structure on the acoustic performance of the transducer are systematically investigated through frequency-domain finite element simulations using COMSOL Multiphysics. The results indicate that increasing the lateral dimension effectively suppresses nontarget modes and improves the smoothness of the frequency response, while the incorporation of a double-layer nonuniform structure enhances the transmit voltage response and broadens the effective bandwidth. Furthermore, the influence of backing materials composed of epoxy resin mixed with varying mass fractions of hollow glass microspheres is analyzed. It is observed that bandwidth enhancement becomes more significant when the acoustic impedance of the backing material is closer to that of the piezoelectric element. The experimental results indicate that the developed transducer prototype achieves a maximum transmit voltage response of 151.9 dB and -3 dB bandwidth of 585 kHz within an operating frequency range of 620-1205 kHz. The proposed design scheme based on P(VDF-TrFE) material holds significant application value in high-frequency broadband aquatic acoustic transducers and serves as a crucial reference for advancements in underwater communication technology.