钴铁氧体磁致伸缩超声换能器设计及输出特性  

Design and output characteristics of cobalt ferrite magnetostrictive ultrasonic transducer

作　　者：姜涛[1] 薛昌盛 皮钧[1] 沈志煌[1] 侯达盘[1] 何金春 JIANG Tao;XUE Changsheng;PI Jun;SHEN Zhihuang;HOU Dapan;HE Jinchun(College of Marine Equipment and Mechanical Engineering,Jimei University,Xiamen 361021,Fujian,China)

机构地区：[1]集美大学海洋装备与机械工程学院,福建厦门361021

出　　处：《陕西师范大学学报（自然科学版）》2024年第6期67-73,共7页Journal of Shaanxi Normal University：Natural Science Edition

基　　金：福建省自然科学基金(2021J01850,2021J01853)。

摘　　要：传统镍基材料和稀土基材料磁致伸缩系数小、涡流损耗大、制备成本高,采用钴铁氧体作为磁致伸缩超声换能器的驱动核心可实现在高频条件下的稳定服役和大功率输出。基于钴铁氧体磁致伸缩特性,设计了谐振频率30 kHz的纵振磁致伸缩超声换能器,使用有限元仿真对钴铁氧体磁致伸缩换能器进行动力学与磁场分析。对钴铁氧体磁致伸缩超声换能器进行阻抗匹配并测试其输出特性,实验测试了样机谐振频率、输出振幅与工作温度。结果表明:换能器采用钕铁硼建立的偏置磁场,磁感应强度为0.1~0.25 T(301~653 Oe),使钴铁氧体处于最佳驱动区内(250~750 Oe);换能器振幅输出和工作温度随着驱动电压的增大而增大,在驱动电压为12 V、信号增益为20 dB条件下换能器实际谐振频率为29.8 kHz,输出振幅可达3.75μm,稳定工作温度60℃,该实验结果验证了钴铁氧体在磁致伸缩换能器领域的可靠性与应用潜力。Compared with the traditional nickel-based materials and rare earth-based materials,the magnetostrictive coefficient is small,the eddy current loss is large,and the preparation cost is high.Utilizing cobalt ferrite as the driving core of magnetostrictive ultrasonic transducer can achieve stable service and high-power output at elevated frequencies.In this paper,a longitudinal magnetostrictive ultrasonic transducer with resonant frequency of 30 kHz is designed based on the magnetostrictive characteristics of cobalt ferrite and the finite element simulation is used to analyze the dynamics and magnetic field of the transducer.The output characteristics of the cobalt ferrite magnetostrictive ultrasonic transducer are tested by impedance matching.The resonant frequency,output amplitude and working temperature of the prototype are tested.The results show that the magnetic field intensity is 0.1~0.25 T(301~653 Oe),which can meet the driving requirement of cobalt ferrite in the best driving range(250~750 Oe).When the driving voltage is 12 V and the signal gain is 20 dB,the actual resonant frequency of the transducer is 29.8 kHz,the output amplitude is 3.75μm,and the stable working temperature is 60℃.The experimental results verify the reliability and application potential of cobalt ferrite in the field of magnetostrictive transducers.

关 键 词：钴铁氧体 磁致伸缩材料 超声换能器 有限元分析 

分 类 号：TB552[理学—物理]