基于1-3型弛豫铁电单晶复合材料与梯度匹配层的高频水听器研究

Underwater transducers are the window of information communication between sonar system and water medium, they behave as the ears and eyes in terms of target detection and positioning. To solve the challenge of detection and precise imaging of small target with weak signals, this research project improves the sensitivity and bandwidth of high-frequency hydrophone by optimizing and integrating the 1-3 relaxor ferroelectric single crystal composites in piezoelectric component and gradient matching layer, respectively. Firstly, according to orientation optimization, the adjusting mechanism of hydrostatic performance for composites based on 1-3 ferroelectric relaxor single crystal will be provided. Secondly, based on the transmission characteristic of gradient matching layer, the balancing method between sensitivity and bandwidth will be presented. Furthermore, for high-precision transducer design，the influence of excitation signal on the center frequency of gradient matching layer under unsteady state is investigated. Finally, optimization of the above composites and gradient matching layer is provided, which lays the theoretical basis for design and manufacture of high-frequency hydrophone with high sensitivity and broad bandwidth.

水声换能器作为声纳系统与水介质信息交流的窗口，是水下目标探测与定位任务的耳目。为解决水中弱信号小目标探测和精细成像问题，本课题通过优化集成基于1-3型弛豫铁电单晶复合材料的压电单元与梯度匹配层，以提升高频水听器的灵敏度并突破带宽瓶颈。具体研究内容如下：基于各向异性弛豫铁电单晶的取向优化，为1-3型复合材料的静水压性能调控提供理论依据；研究梯度匹配层的传输特性，在此基础上提出其灵敏度与带宽的协调方法；揭示非稳态条件下激励信号对梯度匹配层中心频率的偏离规律，实现匹配层的精准设计；最终，获得1-3型压电复合材料与梯度匹配层的集成优化方法，为制备高灵敏度、大带宽的高频水听器提供理论基础。

水声换能器作为声纳系统与水介质信息交流的窗口，是水下目标探测与定位任务的耳目。为解决水中弱信号小目标探测和精细成像问题，本课题通过优化集成基于1-3型弛豫铁电单晶复合材料的压电单元与多层匹配层，以提升高频水声换能器的发送电压响应并突破带宽瓶颈。具体研究内容如下：基于各向异性弛豫铁电单晶的取向优化，为1-3型复合材料的静水压性能调控提供理论依据；研究多层匹配层的传输特性，在此基础上提出其发送电压响应与带宽的协调方法；揭示非稳态与稳态条件下激励信号对水声换能器匹配层的设计准则的影响，从而实现匹配层的精准设计。最终，基于本项目提出的水声换能器匹配层设计的理论模型，制备了宽带的水声换能器样机，测试结果与理论结果吻合良好，验证了理论模型的准确性。