Pulsed eddy current thickness measurement and characteristic extraction of ferromagnetic materials

Based on the COMSOL Multiphysics software, the simulation model of the thickness of the ferromagnetic test piece for pulsed eddy current testing was established by using the finite element method. Then the thickness of the tested piece was changed to simulate the experiment, and the detection voltage signals corresponding to different thicknesses were obtained. Finally, the wall thickness inversion is realized by the peak value of the differential voltage signal, the peak time of the differential voltage signal and the slope of the late signal in the single logarithmic coordinate system. The range and characteristics of the wall thickness of the three feature quantities are compared.