面剪切振动模式弛豫铁电单晶换能器

Relaxation ferroelectric single crystal transducer of face shear vibration mode

[011]极化方向、zxt-45°切型的PIN-PMT-PT单晶因其高剪切压电应变常数、高机电耦合系数和高柔顺系数等特点,在水声换能器中存在广阔的应用前景。通过设计中间质量块的方法,将单晶产生的剪切振动转换为换能器的纵向振动,并利用辐射头的弯曲振动和圆环尾质量块振动的耦合拓宽工作频带。通过有限元仿真分析,研究了结构参数对各阶模态振型和谐振频率的影响。最终仿真得到的换能器工作频带6~18 kHz,最大发送电压响应为138 dB,带内起伏小于4 dB。研究结果表明:采用面剪切工作模式有利于实现换能器低频、小尺寸、宽带发射。

The polarization direction[011],zxt-45°cut PIN-PMT-PT single crystal has a broad application prospect in underwater acoustic transducer due to its high shear piezoelectric strain constant,high electromechanical coupling coefficient and high compliance coefficient.By using an intermediate mass block,the shear vibration generated by the single crystal is converted into the longitudinal vibration of the transducer,and the bandwidth is broadened by the coupling between the bending vibration of the circular piston and the vibration of the ring tail mass block.Through the finite element simulation analysis,the influence of the structural parameters on the vibration modes and resonance frequency is studied.Finally a virtual prototype is determined.The maximum transmitting voltage response is 138 dB with the fluctuation less than 4 dB in the frequency range from 6 kHz to 18 kHz.These results show that the use of the face shear mode is beneficial to achieving low frequency and broadband radiation performance of the transducer with compact size.