The part under test is exposed to the magnetic field created by the test coil. Eddy currents are induced within the electrically conductive material. Additionally the part is magnetized as far as ferromagnetic material is to be tested. The voltage induced in the receiver winding depends on the electrical conductivity (electrical property) as well as on the shape and size of the hysteresis curve (magnetic property). It is analyzed and allows a sensitive test of ferromagnetic as well as non-ferromagnetic and austenitic materials.