Eddy current flaw detector manufacturers use "electromagnetic field theory" as the basic theory of eddy current flaw detection and magnetic particle flaw detection conductor inspection. Eddy currents are caused by a magnetic effect called an electric current. When AC current is released into a conductor, such as a copper transmission line, the magnetic field creates a magnetic field in and around the conductor. Vortex is the flow of electricity caused by magnetic induction, which flows in a ring road. It is often called a "vortex" because it moves in the same way as a liquid or vapor around a blockage in a ring. If a conductor is placed in the converted magnetic field, the eddy current will be created in which conductor, and the eddy current will also create its own magnetic field. Eddy-current detection calibration Eddy-current detector manufacturers design the magnetic field to expand as the alternating current increases and round as the alternating current decreases. Therefore, when the conductor Foerster eddy current flaw detector surface or near the surface of the defects or precise measurement of some characteristics of metal composite material changes, will harm the eddy compressive strength and spread, and then you can test the eddy current transformation status together, In this way, we can indirectly understand the existence of internal defects and whether the characteristics of metal materials have changed.