From the eddy current principle can be seen eddy current detection has the following characteristics:
(1) Eddy current testing is only applicable to conductive materials, if it is non-conductive material, can not sense the eddy-shaped current, it can not use eddy current testing.
(2) Eddy current testing is particularly applicable to the conductive material surface and near surface detection.
(3) Eddy current testing does not require coupling agent. The electromagnetic field excited by the eddy current detection is only an electromagnetic wave. It has the property of fluctuation and particle, so the probe (coil) and the workpiece can be transmitted without coupling, so the non-contact detection can be carried out. This is superior to ultrasonic testing. Because ultrasound is a mechanical wave, can only spread in the material. Therefore, ultrasonic testing must be between the probe and the workpiece by adding coupling agent.
(4) Eddy current testing can achieve rapid and automated testing.
(5) Eddy current testing can be applied to the detection of high-temperature metal, because the metal at high temperature with conductivity.
(6) Eddy current testing is also applicable to the detection of profiled material, as long as the coil can be made into a variety of shapes can be detected.
