Thickness Measurement Using Transient Eddy Current Techniques

This paper describes a pulsed eddy current (PEC) based non-destructive testing system used for experimental evaluation of material thickness and properties. Both classical and modern sensing methods of magnetic field have been carried out. An inductive as well as a giant magnetoresistive sensor based (GMR) probe have been used for sensing and the results obtained are presented and compared. The use of GMRs for this type of application is innovative and the post processing method too, since it evaluates the thicknesses of the conductive samples or of its non-conductive coatings, from the values obtained with the integration of measured signals.