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In order to further understand the characteristics of PMN-PT piezoelectric single crystal materials, the piezoelectric constant d33, impedance and frequency characteristics of PMN-PT piezoelectric single crystal elements under different pressures are studied in this paper, and the performances of PMN-PT piezoelectric single crystal elements are compared with PZT-4 piezoelectric ceramic elements. The non prestressed PMN-PT piezoelectric single crystal sandwich dipole transducer is studied and compared with PZT-4 piezoelectric ceramic sandwich dipole transducer of the same size. The matching layer broadband PMN-PT piezoelectric single crystal circular composite rod transducer is studied. The stress distribution of the transducer under 10 N pressure is calculated, and the problem of local crack of the piezoelectric single crystal element is solved from the structural design. The results show that the PMN-PT piezoelectric single crystal material has obvious advantages in low frequency performance, acoustoelectric and electroacoustic conversion efficiency, and can improve the emission and reception performance of acoustic transducer at the same time. The maximum transmitting voltage response and receiving sensitivity of the non prestressed sandwich dipole transducer can reach 144 dB and −166 dB respectively. Compared with piezoelectric ceramic transducer, the resonance frequency is reduced by about 3 kHz, and the transmitting and receiving performance are improved by 3 dB and 6 dB respectively. The matching layer broadband PMN-PT piezoelectric single crystal circular composite rod transducer has a transmitting voltage response of more than 136 dB, fluctuation of less than 5 dB, receiving sensitivity of more than −176 dB and fluctuation of less than 6 dB in the frequency range from 20 kHz to 40 kHz. The research results of this paper have important reference value and guiding significance for the popularization of PMN-PT piezoelectric single crystal material and its application in acoustic transducer. |
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