基于压电单晶PMNT的溢流环换能器研究

Research on Overflow Ring Transducer Based on Piezoelectric Single Crystal PMNT

摘要:

溢流环换能器是一种高效水平全向的声学换能器，被广泛应用在水声探测和通信等领域。压电单晶材料相比于压电陶瓷具有更高压电系数和换能效率，但由于工艺限制目前只有少量应用。通过理论分析溢流环换能器的谐振频率、发送电压响应和接收灵敏度，表明具有高压电常数的压电单晶可以提高溢流环换能器的发射和接收性能。采用压电单元与铝合金单元交错镶拼结构，制作出基于压电单晶和压电陶瓷 2 种材质的溢流环换能器。提出磁控溅射联合导电胶的电极处理工艺，解决镶拼过程中电极易脱落的难题。将制作的 2 种压电材料溢流环换能器进行声学测试，结果表明基于压电单晶溢流环换能器的发送电压响应和接收灵敏度比压电陶瓷平均高 3 dB 以上。

Abstract:

Overflow ring transducer is an efficient horizontal omnidirectional acoustic transducer that is widely used in underwater detection and communication fields. Compared with piezoelectric ceramics，piezoelectric single crystals have higher piezoelectric coefficient and transducing efficiency，but due to process limitations，they have only been used in a limited number of applications. In this paper，the resonant frequency，transmitting voltage response，and receiving sensitivity of the overflow ring transducer are analyzed theoretically. It is shown that piezoelectric single crystal with high piezoelectric constant can improve the transmitting and receiving performance of the overflow ring transducer. An alternating arrangement of piezoelectric units and aluminum alloy units is used to fabricate overflow ring transducers made of piezoelectric single crystals and piezoelectric ceramics. A process for electrode treatment using magnetron sputtering and conductive adhesive is proposed to solve the problem of electrode loss during assembly. The acoustic performance of the two piezoelectric material overflow ring transducers is tested，and the results show that the transmitting voltage response and receiving sensitivity of the piezoelectric single crystal overflow ring transducer are more than 3 dB higher than those of the piezoelectric ceramic transducer on average.