Study of Meandering Winding Magnetometers on the evaluation of surface hardness on carburized steel

As part of a project to identify nondestructive techniques to determine the surface hardness and case depth of carburized steel, Meandering Winding Magnetometers (MWM) measurements have been evaluated. MWM is based on eddy current testing. Compared to the traditional eddy current testing, MWM integrate the generating coil and detection coil into a thin, flexible sensor which can be applied to complex geometries. Conductivity and permeability are measured with MWM to evaluate the properties of carburized steel. For this study, samples of 1018 and 8620 were carburized to selected hardness and case depths. MWM was determined to be an effect method to detect the surface hardness. In this paper, results of this method will be presented and discussed.