The Impedance of Eddy Current Probes Above Layered Metals Whose Conductivity and Permeability Vary Continuously

Summary from only given, as follows. A numerical method for calculating the impedance of a cylindrical air core probe over a layered metallic half-space is presented. The method permits the conductivity and permeability to vary as arbitrary functions of the depth into the material. The utility and accuracy of the method will be illustrated by comparison: (1) to the available experiment, and (2) go exact results for a conductivity profile that varies as a hyperbolic tangent.