堆叠压电复合材料圆环换能器研究

Research on the stacked piezoelectric composites ring transducer

针对目前换能器亟待扩展带宽的问题,本文通过将两个不同共振频率的圆环进行轴向堆叠产生双模态耦合的方式研制了一种宽带压电复合材料圆环水声换能器的敏感元件。该换能器敏感元件由两个压电复合材料圆环进行轴向堆叠,从而实现厚度方向的双模耦合振动。通过径向切割压电陶瓷圆环、灌注柔性聚合物(如环氧树脂、聚氨酯等)、样品打磨、被覆电极等一系列工艺制备出压电复合材料圆环。再将制备出的相同外径、不同壁厚的压电复合材料圆环进行轴向叠堆,制备出叠堆压电复合材料敏感元件。用制备出的敏感元件通过灌注防水透声层、封装得到的换能器进行水下性能测试。测试结果显示:该换能器谐振频率为410 k Hz,-3 d B带宽达60 k Hz。实现了换能器宽带发射声波的目标。

In view of the problem that the current transducer needs to expand the bandwidth,in this paper,a kind of transducer made of wide band piezoelectric composite material was developed,by axial stacking of two circular rings with different resonance frequencies,the double mode coupling is generated. The transducer sensing element was axially stacked by two piezoelectric composite rings, so as to realize the dual mode coupling vibration in the thickness direction. By a series of workmanship such as cutting piezoelectric ceramic ring,filling in flexible polymer （epoxy resin, polyurethane, etc.）,grinding sample,coating electrode, etc.,the piezoelectric composite ring was made. Later,rings with the same outer diameter and different thicknesses were stacked together along the axial di-rection for fabricating sensitive elements made of stacked piezoelectric composites. The transducer was processed by filling in with a waterproof sound transparent layer and sealing for forming a transducer. The transducer was tested for its underwater performances. The experimental results show that the resonant frequency of the transducer is 410 kHz,the bandwidth of -3 dB is 60 kHz,and the target of broadband transmission for sound waves is realized.