Comparison Of Pec And Sfec Nde Techniques

Abstract

Eddy current testing is one of the most widely used Nondestructive Evaluation (NDE) techniques. The recent development of multiple frequency and Pulsed Eddy Current (PEC) NDE has demonstrated high potential for applications in quantitative NDE in terms of defect profiles, defect depths and 3D defect reconstruction in particular. This paper systematically investigates eddy current behaviour in the frequency domain. Two methods, Swept Frequency Eddy Current (SFEC) and PEC are comparatively studied with respect to their capability to discriminate among various test cases. It is demonstrated that using PEC we can discriminate among the upper and reverse surface slots, as well as various sample thicknesses, with resolution compatible to SFEC at single excitation cycle.

Keywords:

• nondestructive evaluation
• pulsed eddy currents
• swept frequency eddy currents
• frequency domain

Acknowledgements

This work was funded by an EPSRC grant [EP/E005071/1]. The authors would like to express their gratitude to QinetiQ Ltd. for providing the TRECSCAN® PEC system for the study. TRECSCAN is a Registered Trademark of QinetiQ Ltd.