Signal Strength Enhancement of Magnetostrictive Patch Transducers for Guided Wave Inspection by Magnetic Circuit Optimization
Signal Strength Enhancement of Magnetostrictive Patch Transducers for Guided Wave Inspection by Magnetic Circuit Optimization
复制标题
通过磁路优化增强导波检测磁致伸缩贴片传感器的信号强度
DOI：
10.3390/app9071477
复制
发表时间：
2019-04-01
影响因子：
2.7
通讯作者：
Lv, Fuzai
中科院分区：
文献类型：
--
作者：
Wu, Jianjun;Tang, Zhifeng;Lv, Fuzai
带平面线圈的磁致伸缩贴片传感器 (MPT) 具有灵活性、轻便性和良好的方向性等优点，是管道和板材检测中剪切模式生成和检测的理想选择。然而，能量转换效率低限制了MPT在长距离检测中的应用。在本文中，提出了一种使用软磁贴片（SMP）进行动态磁场优化来增强 MPT 的方法。 SMP可以降低磁路的磁阻，从而增加了波产生过程中磁致伸缩贴片中的动态磁场强度，并限制了波检测过程中用于传感的线圈周围区域内的感应动态磁场。在不同频率下进行的数值模拟验证了SMP对动态磁场的改善以及不同影响因素的影响。在铝板中进行了波生成和检测中信号增强的实验验证。当MPT被SMP覆盖时，幅度放大可以达到12.7 dB。根据数值和实验结果，在满足其他应用条件的情况下，推荐使用相对磁导率和厚度较大且SMP与线圈紧密贴合的SMP。
Magnetostrictive patch transducers (MPT) with planar coils are ideal candidates for shear mode generation and detection in pipe and plate inspection with the advantages of flexibility, lightness and good directivity. However, the low energy conversion efficiency limits the application of the MPT in long distance inspection. In this article, a method for the enhancement of the MPT was proposed by dynamic magnetic field optimization using a soft magnetic patch (SMP). The SMP can reduce the magnetic resistance of the magnetic circuit, which increases the dynamic magnetic field intensity in the magnetostrictive patch during wave generation and restricts the induced dynamic magnetic field within the area around the coils for sensing during wave detection. Numerical simulations carried out at different frequencies verified the improvement of the dynamic magnetic fields by the SMP and influence of different affecting factors. The experimental validations of the signal enhancement in wave generation and detection were performed in an aluminum plate. The amplitude magnification could reach 12.7 dB when the MPTs were covered by the SMPs. Based on the numerical and experimental results, the SMP with a large relative permeability and thickness and close fitting between the SMP and coils were recommended when other application conditions were met.