弛豫铁电单晶矢量水听器研究

Vector hydrophone is a new type of underwater acoustic measurement sensor, which can measure acoustic pressure and velocity. it is a difficult to improve the performance of the vector hydrophone for the property of the piezoelectric ceramic. In recent years, the relaxor ferroelectric single crystal is studied as a new type of piezoelectric material, which has excellent piezoelectric properties and promising application perspective. In this project, the relaxor ferroelectric single crystal vector hydrophone is proposed and studied. The analysis method of the hydrophone is studied according to the anisotropic characteristic of the single crystal. The cuts and oritention of the single crystal is analyzed to calculated the influence on the performance of the vector hydrophone. Based on the modle of different cuts of single crystal vector hydrophone, the matching problem between the single crystal and the structure is studied. On this basis, the single crystal vector hydrophone with high sensitivity and low self-noise will be developed.

矢量水听器是一种新型的水声测量传感器，它不但能够测量声场的声压信息，而且能够测量声场的矢量信息（质点振速、质点加速度和声压梯度）。近年来国内外对矢量水听器进行了大量研究，但是受到压电陶瓷材料本身性能的限制，在进一步提高矢量水听器的灵敏度、降低自噪声等方面存在较大的难度。弛豫铁电单晶是一种新型的压电材料，具有优异的压电性能，在水听器性能的提高方面具有巨大的潜力。因此本课题利用新型弛豫铁电单晶材料开展矢量水听器的研究工作。通过对弛豫铁电单晶各向异性特性的研究，分析弛豫铁电单晶矢量水听器的建模分析方法。研究弛豫铁电单晶切型及单晶性能取向对矢量水听器灵敏度及自噪声的影响。对不同切型的单晶矢量水听器进行建模分析，研究弛豫铁电单晶材料与矢量水听器结构的匹配问题。最终研制出高灵敏度、低噪声的弛豫铁电单晶矢量水听器样品。

本课题利用新型弛豫铁电单晶压电材料开展高性能矢量水听器的研究工作。推导了矢量水听器的声场互易理论和机电等效网络，为弛豫铁电单晶矢量水听器的建模及仿真工作提供了理论支撑。系统研究了[001]及[110]切型弛豫铁电单晶样品的材料特性，重点分析了单晶材料压电常数的分布规律。. 在理论分析及材料研究的基础上，提出利用多层复合悬臂梁结构研制弛豫铁电单晶高性能矢量水听器的设计思想。利用有限元模型分析了矢量水听器的低频振动特性及接收特性，重点研究了各向异性弛豫铁电单晶材料与悬臂梁结构的匹配问题。在此基础上研制了二维弛豫铁电单晶矢量水听器样机。矢量水听器样机工作频率10Hz—1kHz，具有良好的偶极子指向性,等效接收声压灵敏度达到-182dB左右，比普通压电陶瓷材料提高近12dB，自噪声比普通压电陶瓷材料低2dB左右。. 课题总计发表文章2篇，其中1篇EI检索，1篇核心期刊。