飞机铆接件隐藏缺陷的远场涡流检测探头优化与试验

Optimization and experimentation of remote field eddy current testing probe for hidden defects of aircraft riveting parts

远场涡流检测技术因检测深度深和检测结果可靠性高等诸多优点适合飞机多层金属铆接构件的快速检测。针对飞机铆接件铆钉孔沿边隐藏裂纹的原位检测,建立了多层金属铆接构件隐藏缺陷平面远场涡流检测有限元模型,对激励线圈内径、磁路结构以及屏蔽阻尼进行了仿真优化,研制了激励线圈和检测线圈均带组合屏蔽结构的传感器,采用激励-检测线圈环绕铆钉旋转扫描的方式,研究多层金属铆接构件铆钉孔沿边隐藏裂纹信号特征。仿真与试验结果表明:罐形磁芯聚磁效果是柱形磁芯的1.85倍,采用铝+铜组合屏蔽罩能够将远场区提前10mm,检测线圈位于缺陷正上方时,检测信号的幅值和相位存在极大值,且极大值随着缺陷埋深的增加逐渐下降,研究成果可望用于指导飞机多层金属铆接构件的工程检测实践。

The remote field eddy current testing technique features a deep depth of detection,high reliability of detection results,and many other advantages,which make it suitable for rapid detection of multi-layer metal riveting components.Aiming at the in-situ detection of hidden cracks along the rivet holes of aircraft riveting,the finite element model for the remote field eddy current detection of the hidden crack plane of multi-layer metal riveting members is established.The inner diameter of exciting coli,magnetic circuit structure,and shielding damping are simulated and optimized.The exciting coil and the detecting coil are combined with the shielding structure.The characteristics of hidden crack signals along the rivet holes of multi-layer metal riveting members are studied.The simulation and experimental results show that the tank shape of the magnetic core is 1.85 times that of the cylindrical of the magnetic core.The shield of the aluminum cover+ copper cover can advance the remote field by 10 mm.When the detection coil is directly above the defect,the detected amplitude of the signal value and phase reach the maximum values.And the maximum value decreases with the increase of the buried depth of the defect.The research results are expected to be used to guide the engineering inspection practice of the multi-layer metal riveted components of the aircraft.