The principle of detecting coating thickness by eddy current method

       The working principle of the eddy current method is to use a probe carrying a high-frequency current coil to generate a high-frequency magnetic field on the surface of the test sample, which causes eddy currents inside the metal coating, and the magnetic field generated by this turbulent current reacts on the coil in the probe, making it The thickness of the coating is determined by detecting the eddy current loss of the coating. The thickness gauge is not limited by the ferromagnetism of the workpiece, and a standard sample is required for reading calibration. In order to make the measurement results as accurate as possible, the advertised thickness, material, surface state, uniformity, etc. should be consistent with the coating as much as possible. Commonly used eddy current thickness gauges are JWH-1, JWH-2, 7504 type and so on.