The induced current method also called "EDDY currents", operates under the principle of electromagnetic induction, where an alternating magnetic field induces current on the test piece if it is a conductive material.
It is a non-destructive test method since its application does not alter in any way the properties of the object under study. It is a superficial test, it detects sub-superficial defects.
The pattern of Eddy currents and the magnetic field that is necessarily associated with them are influenced by different characteristics of the material under test. These characteristics can be grouped into three groups: Detection of discontinuities, measurement of material properties and dimensional measurements.