Design of a flexible eddy current probe in view of the evaluation of the electrical conductivity during inspection of defects

There are several methods for the evaluation of the electrical conductivity of a material but many of them are difficult to implement in an industrial context. The aim of this study is to develop a non-contact probe to evaluate the electrical conductivity during the inspection of defects in the case of purely conductive materials. For this purpose the eddy current testing method is used. In this study, the comparison between several probe configurations is performed to reduce the lift-off effect. All simulations were performed with the simulation platform CIVA. An optimized probe was realized according to the following criterion: get a straight response of the probe in the complex plane when the electrical conductivity evolves. The probe is evaluated experimentally on conductivity standards and materials with surface defects. The experimental measurements show a good fit with the simulated results obtained by CIVA. In a single measurement, the evaluation of the electrical conductivity and the inspection of defects is achieved.