Advantage analysis of PMN-PT material for free-flooded ring transducers

The acoustic radiation characteristics of free-flooded ring transducers made of PZT4 and PMN—PT materials are calculated and compared. First, the theoretical formulae for free-flooded ring transducers are studied. The resonant frequencies of a transducer made of PZT4 and PMN—PT materials are calculated. Then, the transmitting voltage responses of the free-flooded ring transducers are calculated using the finite element method. Finally, the acoustic radiation characteristics of the free-flooded ring transducers are calculated using the boundary element method. The calculated results show that the resonant frequencies of the free-flooded ring transducer made of PMN—PT are greatly reduced compared with those made of PZT4 with the same size. The transmitting voltage response of the transducer made of PMN—PT is much higher than that of the transducer made of PZT4. The calculated 3-dB beamwidth of the acoustic radiated far-field directivity of the free-flooded ring transducer made of PZT4 at the resonant frequency 1900 Hz is 63.6° and that of the transducer made of PMN—PT at the resonant frequency 1000 Hz is 64.6°. The comparison results show that the free-flooded ring transducer made of PMN—PT material has many advantages over that made of PZT4. The PMN—PT is a promising material for improving the performance of free-flooded ring transducers.