Specific features of double-differentiation eddy current probe signals from inclined cracks

Keywords

eddy current transducer, signal hodograph in complex plane, inclination of the crack, informative parameters, aluminum alloy.

Cite as

Uchanin V. M. Specific features of double-differentiation eddy current probe signals from inclined cracks. Physicochemical Mechanics of Materials. 2025. 61(2), 139-144.

https://doi.org/10.15407/pcmm2025.02.139

Abstract

The features of the hodographs of the signals of a low-frequency eddy current (EC) probes of double-differentiation type with an operational diameter of 6 mm in the complex plane during scanning of a layered aluminum alloy specimen with artificial crack-like defects oriented at different angles of inclination to the tested surface were investigated. The research was conducted at an operational frequency of 6 kHz using an eddy current board of the EDDYMAX type. The features of the hodographs were analyzed depending on the inclination, depth of the location and the lift-off between the EC probe and the specimen surface. Based on the analysis of the shape of the hodographs from defects of different inclinations, informative parameters were proposed which correlate with the inclination of the defect, in particular, the width of the hodograph or the area of the contour covering it, which for a perpendicular defect are equal to zero and increase with inclination angle decrease. The proposed information parameters can become the fundamentals for evalua-ting the parameters of inclined cracks during eddy current testing.

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