A method for simultaneously measuring the resistivity, permeability and thickness of a moving metal sheet with a double coil

A method to determine the resistivity, permeability and thickness of moving magnetic sheets is described. The parameters of a sample sheet inserted between two coils facing each other are determined by measuring the impedance of the two coils at two different frequencies, By using the difference in the impedance of the coils between two cases, i.e., the current passes through the coils in the same direction and in opposite directions to each other, the experimental data can be compared with theoretical values, The method was tested by measuring the resistivity, permeability and thickness of a nickel sheet of 1 mm thick moving at velocities varying from 0 to 6 m/s. It was possible to accurately determine the resistivity, permeability and thickness within 3% at two different frequencies of 400 and 800 Hz