带匹配层的复合材料三圆管堆叠圆柱阵换能器

Underwater acoustic transducer is signal transceiver device for underwater detection and communications, it is underwater "radio", the band width and the beam-width is two performance indexes of the transducer, expanding the bandwidth and increasing the beam-width is always the main problem of the transducer.. to increase the beam-width, it can use cylindrical surface transducer. to extend the bandwidth of the transducer, there is the following three ways: ① using Composite materials as active materials; ②the ingenious design of sensitive element structure to produce vibration and realize multimode coupling; ③ Coating matching layer..At present, because of the limitation of the curved surface of the composite material, the existing cylindrical transducer generally uses pure piezoelectric ceramics as the active material, which directly leads to the lack of bandwidth..This project uses piezoelectric composite material as the active material, and adopts three tube of same diameter and different thickness which is stacking alone the axial, thus the multimode vibration can be produced, after that, the matching layer is coated on the external. Through the rational design of the structural dimensions of three composite circular tubes and the material mixed ingredients and thickness of the matching layer, it can realize the coupling of multiple vibration modes, so as to maximize the bandwidth of the transducer.The structure of the transducer has not been reported at home and abroad. it not only has a wider bandwidth, but also has the characteristics of large beam angle, which can make up for the shortage of the existing transducer.

水声换能器是用于水下探测和通讯的信号收发器件，是水下“电台”，频带宽度和波束开角是换能器的两个性能指标，拓宽换能器带宽和增大波束开角一直是换能器研究的主要问题。.增大波束开角可以通过采用柱型等曲面换能器实现，扩展换能器的带宽可以通过以下方式实现：①用复合材料作为有源材料；②巧妙设计敏感元件结构使其产生多模振动并实现耦合；③被覆匹配层。.目前，由于受复合材料曲面成型的限制，现有圆柱换能器一般都采用纯压电陶瓷作为有源材料，这样直接导致其带宽不足。 .本项目采用压电复合材料作为有源材料，同时在结构上采用外径相同、厚度不同的三个圆管轴向堆叠，使其产生多模振动，并在其外围被覆匹配层；合理设计三个复合材料圆管的结构尺寸和匹配层的材料配方与厚度，可使其实现多个振动模态的耦合，进而最大限度的拓宽换能器的带宽。.该结构换能器国内外未见报道，它具有较宽的带宽，同时兼有大波束开角的特点，可弥补现有换能器的不足。

项目以拓展带宽和增大水声换能器的水平波束开角为研究目标。通过圆柱状结构增大拓展换能器波束开角；以压电复合材料作为有源材料，采用三环轴向叠堆产生模态耦合和添加匹配层的方式拓展换能器的带宽。通过研究项目建立带匹配层的叠堆复合材料敏感元件的理论模型，推导出敏感元件谐振频率、机电耦合系数等与组成敏感元件各结构尺寸、材料配比的关系，进而得到在换能器其它性能不降的情况下，最大限度拓宽带宽的设计方案。经实验建立了换能器敏感元件的工艺流程，通过切割-浇注-曲面成环等工艺制备出内半径不同、外半径相同的压电复合材料圆环，并将不同壁厚的圆环轴向叠堆制成换能器样机。样机最大发送电压响应163.4dB（预期研究成果发送电压响应>160dB），-3dB频带范围：330kHz~430kHz（预期研究成果带宽>70kHz），在带宽工作范围内，声源级大于195dB（预期研究成果 180dB），水平指向性开角（-6db）为360°（预期研究成果指向性：水平全向）。项目研究的相关技术获得4项国家发明专利授权；研究成果发表论文16篇，其中SCI检索7篇，EI检索1篇。