一种高灵敏压电平面水声换能器

A high sensitive piezoelectric planar underwater acoustic transducer

设计并制作了一种高灵敏压电平面水声换能器。该换能器敏感元件是对1-3-2型压电复合材料结构的改进,即在带基底的压电陶瓷小柱阵列间不注入聚合物,并在其上表面直接覆盖金属板,构成“带基底的压电小柱阵列+金属盖板”结构敏感元件(称为“空气填充型”敏感元件)。对“空气填充型”敏感元件的谐振频率进行了理论计算和有限元仿真,与实测结果较吻合。为便于对比性能,同时制作了同尺寸“1-3-2型压电复合材料+金属盖板”结构敏感元件(称为“聚合物填充型”敏感元件)换能器。分别对“空气填充型”和“聚合物填充型”敏感元件换能器的有效机电耦合系数、发送电压响应和接收灵敏度进行有限元仿真和实测,结果均显示,“空气填充型”敏感元件换能器具有较高的接收灵敏度,相较于“聚合物填充型”敏感元件换能器可提高21 dB。该敏感元件换能器能有效提高灵敏度,可为研制高灵敏换能器提供参考。

A piezoelectric planar transducer with high sensitivity is designed and fabricated.The transducer sensing element is an improvement of the 1-3-2 type piezoelectric composite structure.The piezoelectric ceramic column array with a substrate is not injected with polymer,and the upper surface is directly covered with a metal plate,then the structure of "piezoelectric column array with substrate+ metal cover plate" sensitive element(called "Air filled"sensitive element) is formed.The resonant frequency of the "Air filled" sensor is calculated theoretically and simulated by finite element method,which is in good agreement with the measured results.In order to compare the performances,the transducer with the structure of "1-3-2 type piezoelectric composite+metal cover plate,"(called "Polymer filled"transducer) is made.The effective electromechanical coupling coefficient,transmitting voltage response and receiving sensitivity of "Air filled" and "Polymer filled" sensor transducers are simulated and measured respectively.The "Air filled" transducer has a higher receiving sensitivity,which can be increased by 21 dB compared with the "Polymer filled"transducer.The transducer can effectively improve the sensitivity,which can provide a reference for the development of high-sensitivity transducer.