Sun Zhenguo, Cai Dong, Zou Cheng, Zhang Wenzeng, Chen Qiang
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
Yangtze Delta Region Institute of Tsinghua University, Jiaxing 314006, China.
Sensors (Basel). 2016 Jun 23;16(7):952. doi: 10.3390/s16070952.
A reliable and accurate inspection of the hollow axle inner surface is important for the safe operation of high-speed trains. In order to improve the reliability of the inspection, a flexible arrayed eddy current sensor for non-destructive testing of the hollow axle inner surface was designed, fabricated and characterized. The sensor, consisting of two excitation traces and 28 sensing traces, was developed by using the flexible printed circuit board (FPCB) technique to conform the geometric features of the inner surfaces of the hollow axles. The main innovative aspect of the sensor was the new arrangement of excitation/sensing traces to achieve a differential configuration. Finite element model was established to analyze sensor responses and to determine the optimal excitation frequency. Experimental validations were conducted on a specimen with several artificial defects. Results from experiments and simulations were consistent with each other, with the maximum relative error less than 4%. Both results proved that the sensor was capable of detecting longitudinal and transverse defects with the depth of 0.5 mm under the optimal excitation frequency of 0.9 MHz.
对空心轴内表面进行可靠且准确的检测对于高速列车的安全运行至关重要。为提高检测的可靠性，设计、制作并表征了一种用于空心轴内表面无损检测的柔性阵列涡流传感器。该传感器由两条激励迹线和28条传感迹线组成，采用柔性印刷电路板（FPCB）技术制作，以贴合空心轴内表面的几何特征。传感器的主要创新点在于激励/传感迹线的新布局，以实现差分配置。建立了有限元模型来分析传感器响应并确定最佳激励频率。在带有若干人工缺陷的试样上进行了实验验证。实验结果与模拟结果相互吻合，最大相对误差小于4%。两者结果均证明，在0.9 MHz的最佳激励频率下，该传感器能够检测深度为0.5 mm的纵向和横向缺陷。
