脉冲涡流厚度检测仿真与实验研究

基于瞬态磁场的轴对称特性，利用有限元方法建立了脉冲涡流厚度检测的理论模型。仿真分析了被测金属板材在不同电导率和厚度参数时的探头差分信号并选择探头差分信号峰值作为信号特征。经分析发现：电导率一定时，差分信号峰值随被测金属板材厚度的增加呈递增趋势；被测金属板材厚度相同时，电导率越大差分信号峰值就越大。运用建立的试验系统进行实验研究，结果表明，实验与仿真结论一致，表明了所建模型的正确性和仿真结果的可信性。

Simulation and Experimental Investigation of Thickness Measurement Using Pulsed Eddy Current Technique

A 2D finite-element model is established for thickness measurement using pulsed eddy current(PEC) technique due to axisymmetric of transient magnetic field. The PEC differential signals were calculated using the de?veloped theoretical model for sheets with different conductivity and thickness. Through analysis on PEC signals due to samples,the peak amplitudes are considered as the desirable signal features for thickness evaluation. The simula?tion results show that the peak value of the PEC differential signal increases when the sheet under test becomes thicker. The metal sheet with higher conductivity also makes the peak value of PEC differential signal larger as well. The observations from the experimental measurements agree well with those from simulation data,which validates the developed model and the simulated results.