Eddy Current Corner Crack Inspection

The purpose of this paper is to report on the development of an eddy current (EC) measurement model applicable to corner crack inspections. Naturally, corner cracks are more difficult to detect than those on flat surfaces, because the specimen edge itself gives a large response to the EC probe. The flaw signal, if any, tends to be obscured by the large edge signal. Thus, probe impedance should be determined more accurately than usual in order to extract flaw signals out of the background. Experimentally, this requires high-accuracy impedance measurements with rigid control over probe motion. In modeling point of view, this means that predictions should be made from an exact model, or at least from a model which can achieve the required level of accuracy [1–3]