Analysis of V-Crack magnetic flux leakage characteristics based on magnetic charge

For technical aspect of ferromagnetic components crack damage detect methods and instruments applications, in this paper the magnetic flux leakage analysis model for V-Cracks was established based on the theory of magnetic charge, the theoretical expressions for any probe point of flat ferromagnetic component surface were obtained. By using MATLAB software to do a comprehensive simulation, the relation curve between magnetic flux leakage normal component Hy and crack opening width, the relation curve between magnetic flux leakage normal component Hy and crack depth, the relation curve between magnetic flux leakage normal component Hy and crack length were obtained; crack magnetic flux leakage distribution characters: normal component of Hy with zero-crossing, tangential component Hx have maximum value, tangential component Hz with tip zero-crossing were obtained. According to the leakage magnetic characteristics obtained under the theoretical analysis, array type detection device and test platform were designed and fabricated for the detection on the flat iron with V-Cracks. Experimental results show that: the three dimensional magnetic flux leakage obtained from thesis theoretical analysis is in accordance with the test results; to a certain extent, the magnetic flux leakage model have directive significance for the prediction and analysis of crack parameters.