飞机铆接构件PRFECT探头的线圈夹角影响

远场涡流检测技术不受集肤效应影响，对金属铆接构件隐藏缺陷检测具有巨大优势。针对飞机金属铆接构件的远场涡流检测，建立了铆接构件隐藏缺陷检测三维模型，分析不同屏蔽阻尼材料及组合方式的屏蔽性能，采用激励线圈与检测线圈均环绕铆钉旋转的检测方法，对比激励线圈-铆钉-检测线圈夹角为90°、135°和180°时缺陷检测灵敏度，研究不同缺陷尺寸检测信号特征。仿真与试验结果表明：当屏蔽阻尼为铝+铜时具有最佳屏蔽性能，且远场区距离激励线圈中心最近；当激励线圈和检测线圈间距为30 mm时，激励线圈-铆钉-检测线圈夹角为180°时检测效果最佳；优化后的探头可检测埋深为6 mm、长×宽×深尺寸为5 mm×0.2 mm×1 mm的铆接构件隐藏缺陷，缺陷信号幅值与其体积当量关系相对应，且随缺陷长度及深度的增加呈上升趋势。

Influence of coil angles of PRFECT probe of aircraft riveting component

The plate remote field eddy current testing technology is not affected by the skin effect, and has great advantages in detecting hidden defects in metal riveting components. For the remote field eddy current testing of metal riveting components of aircraft, a three-dimensional model for detecting hidden defects of riveting components is established, and the shielding performance of different shielding damping materials and combinations of the materials are analyzed. By adopting the detection method that both the excitation coil and the detection coil rotate around the rivet, the defect detection sensitivities when the angle of the excitation coil-rivet-detection coil is 90°, 135° and 180° is compared, and the detection signal characteristics of different defect sizes are studied. The simulation and test results show that it has the best shielding performance when the shielding damping is composed of aluminum and copper, and the remote field area is the closest to the center of the excitation coil. When the distance between the excitation coil and detection coil is 30 mm, the best detection effect is obtained when the angle of excitation coil-rivet-detection coil is 180°. The optimized probe can detect the hidden defects of riveting components with the buried depth of 6 mm and the size of length×width×depth of 5 mm×0.2 mm×1 mm. The amplitude of defect signal corresponds to its volume equivalent relation, and increases with the increase of defect length and depth.