Experimental Study of a Sensor Capable of Increasing the Penetration Depth of Eddy Currents

10.6919/ICJE.202205_8(5).0086

Chengkai Ye；Siquan Zhang

Eddy Current Detection ； Penetration Depth ； Phase-shifted Field Probe ； Theoretical Derivation ； Experimental Demonstration

International Core Journal of Engineering

8卷5期（2022 / 05 / 01）

672 - 681

英文

Eddy current inspection methods are widely used in defect detection and non-destructive evaluation of conductive materials. Due to the skinning effect, conventional eddy current inspection methods can only detect shallow locations on the surface of conductors. A new type of phase-shifted field probe has been proposed and experimentally verified to detect defects deeper than the conventional method. An exact theoretical expression for the distribution of eddy currents within a conductor has also been derived from a theoretical perspective. In this paper, the effectiveness of the probe in detecting defects at different depths is investigated in depth from both theoretical and experimental perspectives. It is verified that the probe design and excitation method can indeed change the eddy current density distribution in the conductor and provide better results for deeper defects than the conventional eddy current detection method.

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