基于柔性电磁传感器的发动机叶片微缺陷检测技术

摘要

飞机发动机叶片由于工作条件恶劣，容易出现疲劳和微缺陷，采用传统的检测方法难以对它们进行准确检测.针对装备复杂结构微损伤的检测问题，论文提出了一种基于柔性电磁传感器和数字锁定检测算法的微缺陷检测技术，在分析柔性阵列式电磁传感器特性的基础上，重点对传感器转移阻抗的数字锁定检测方法和检测数据处理方法进行了研究.搭建了检测平台，并通过实验验证了检测效果.实验结果表明，传感器转移阻抗测量幅度测量的重复精度达到0.04%，相位测量的重复精度达到0.02%.通过对传感器转移阻抗幅度和相位变化量的分析，准确地检测出了宽度为0.1 mm的微裂纹.%Owing to the execrable working conditions,fatigues and micro damages are easy to appear in engine blades,which are difficult to be detected correctly with traditional testing methods.In order to test the micro damages in equipments with complex structure,a micro damage testing method based on flexible electromagnetic sensor and digital locked-in detection algorithm was proposed in this paper. Based on analyzing the flexible array electromagnetic sensor’s characteristics,digital lock-in detection method and detection data processing methods of the sensor's transfer impedance were studied emphati-cally.The testing platform was built and the testing effect was validated with experiments.The experi-mental results indicate that the repetition accuracy of trans-impedance amplitude and phase are 0.04%and 0.02% individually.The micro crack with 0.1 mm width can be detected by the method of the am-plitude and phase variation analysis of trans-impedance.