Tunnel magnetoresistive (TMR) devices have superior performances in weak magnetic field detection. In this study, TMR devices\nwere first employed to form a circular magnetic flux leakage (MFL) sensor for slight wire rope flaw detection. Two versions of this\ntailor-made circular TMR-based sensor array were presented for the inspection of wire ropes with the diameters of 14mm and\n40 mm, respectively. Helmholtz-like coils or a ferrite magnet-based magnetizer was selected to provide the proper magnetic field,\nin order to meet the technical requirements of the TMR devices. The coefficient of variance in the flaw detection performance\nof the sensor array elements was experimentally estimated at 4.05%. Both versions of the MFL sensor array were able to detect\nmultiple single-broken wire flaws in the wire ropes. The accurate axial and circumferential positions of these broken wire flaws\nwere estimated from the MFL scanning image results. In addition, the proposed TMR-based sensor array was applied to detect the\nMFL signal induced by slight surface wear defects. Amutual correlation analysis method was used to distinguish the signals caused\nby the lift-off fluctuation from the MFL scanning image results. The MFL sensor arrays presented in this study provide inspiration\nfor the designing of tailor-made TMR-based circular sensor arrays for cylindrical ferromagnetic structural inspecti
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