A Planar Structure for Eddy Current Non-Destructive Evaluation

A planar structure with a lumped capacitor for eddy current non-destruction evaluation (NDE) is investigated in this paper. Compared with traditional NDE technique using coils, our proposed structure is planar and can be able to form a uniform magnetic field on the surface. The working frequency is 100 kHz and a lumped capacitor is used for optimizing the magnetic field above the plate. When a metal plate is placed in this kind of magnetic field, the eddy current will be induced on the surface of the metal. If a metal plate scratched is placed in the same field, different eddy current will be induced and the port impedance of the structure will be modified. Simulation results show the amplitude of the port current for different metal plates.