In order to boost the electromechanical coupling factor and decrease the characteristic impedance, a 1-3 piezoelectric composite with a 3-tier polymer structure was designed and fabricated, in which epoxy resin constitutes the middle layer and silicone rubber is used to clamp the epoxy. The effective parameters of the composite, such as resonant frequency, electromechanical coupling factor, and characteristic impedance, were studied by the finite element method and experiment. The experimental results indicate that the electromechanical coupling factor of the composite is enhanced by 8.4% and the characteristic impedance is decreased by 52.8%, compared with the traditional 1-3 ceramic/epoxy composite.

A wide-band cylindrical transducer was developed by using the wide band of the composite material and the matched matching layer for multimode coupling. Firstly, the structure size of the transducer’s sensitive component was designed by using ANSYS simulation software. Secondly, the piezoelectric composite ring-shaped sensitive component was fabricated by the piezoelectric composite curved-surface forming process, and the matching layer was coated on the periphery of the ring-shaped piezoelectric composite material. Finally, it was encapsulated and the electrodes were drawn out to make a high-frequency broadband horizontal omnidirectional water acoustic transducer prototype. After testing, the working frequency range of the transducer was 230–380 kHz, and the maximum transmission voltage response was 168 dB in the water.

This paper describes the fabrication of 1-3 piezoelectric composites by using PZT5-A pure piezoelectric ceramics and the preparation of a high-frequency single-directional planar underwater ultrasound transducer by using the developed composites. First, three material models of the same size were designed and simulated by ANSYS finite element simulation software. Next, based on the simulation results, the 1-3 piezoelectric composites were developed. Finally, a high-frequency single-directional planar underwater ultrasound transducer was fabricated by encapsulating and gluing the 1-3 piezoelectric composites. The performance of the transducer was tested, and results showed that the device was characterized by single-mode operation in the working frequency band, a high transmitting voltage response, and single directivity.

A piezoelectric composite vibrator with a bilaminated structure is designed and fabricated, in this work by applying bending vibration to increase vibration displacement and reduce resonance frequency. The finite element software ANSYS (ANSYS, Inc. USA) is used to simulate the 2-2 and 1-3 piezoelectric composite bilaminated vibrators under free boundary condition and optimize their design. Simulation results show that the vibration displacement of the 2-2 vibrator is higher than that of the 1-3 vibrator, and the resonance frequency of the former is lower than the latter. Five pieces each of the 2-2 and piezoelectric ceramic vibrators are prepared. In addition, simulation and experimental results indicate that the vibration displacement of the 2-2 vibrator increases by 2.3 times, whereas its resonance frequency decreases by nearly 100 Hz, in comparison with those of the piezoelectric ceramic bilaminated vibrator.

The bandwidth of composite transducer was successfully expanded via matching layer design. Firstly, the admittance equation of transducer was deduced through combining the equivalent model of 1–3 piezoelectric composite with the electromechanical equivalent circuit of piezoelectric crystal thickness vibration. Then, the relations between bandwidth and the parameters of matching layer were summarized by the conductance curves. Finally, a composite transducer with matching layer was designed and fabricated. Experimental results show that the bandwidth reaches to 56 kHz and the mechanical quality factor Q drops to 1.8. The results are in agreement with the theoretical calculation.

This paper presents an arc broadband piezoelectric composite vibrator and its transducer array. The arc broadband piezoelectric composite vibrator was fabricated by 1-3 piezoelectric composite with matching layer and was prepared by the curved forming process. The vibration characteristics of a new vibrator were simulated via finite element analysis (FEA) and investigated by experiment. First, the acoustic impedance and thickness of the optimized matching layer were determined by theoretical analysis. Second, the arc piezoelectric vibrator was modeled and simulated in air conditions by the FEA method, and the variation law of resonant frequency was analyzed. Finally, the fabrication process of the arc broadband piezoelectric composite vibrator and its transducer array was studied, and the experimental sample was fabricated and measured. The bandwidth of the arc broadband transducer array was found to be up to 56.5 kHz. Results show that the experimental results were in accordance with the simulation results and have good directivity to realize the purpose of bandwidth and beam expansion.