Flexible Floral Eddy Current Probe for Detecting Flaws in Metal Plate

In this work, multiple floral eddy current probes (FECP) are proposed. FECP consists of a detection coil and a plurality of symmetric excitation coils, and due to the number of excitation coils, it could be classified into 4-coils, 6-coils, 8-coils, or 10-coils FECP. Due to the innovation of its configuration that transmitter (TX) coils are successively connected in reverse order and distributed symmetrically around receiver (RX) coil, the proposed new probe is not only less sensitive to the change of the lift-off distance but also has high accuracy and sensitivity of detection and could resist vibration interference. In this paper, the theoretical model of FECP is established, and simulation and experiment verification are carried out respectively. Firstly, the lift-off effect is studied. Moreover, an aluminum tested plate with artificial flaws is used to evaluate the performance of different-type of flexible FECP, which shows higher sensitivity in flaws than the conventional single coil.