A fast method for rectangular crack sizes reconstruction in magnetic flux leakage testing

Magnetic flux leakage (MFL) testing is widely used to examine ferromagnetic materials. For the reason of estimating the sizes of cracks in metals is important in piping industries, a fast method based on particle swarm optimization algorithm is proposed for reconstructing the sizes of rectangular crack in this article. Considering the magnetic leakage field intensity is related to the air gap between the inspection specimen and the sensor, we give the reconstruction results in different lift-off values. Besides, the influence of different magnetic conditions to the reconstruction effectiveness has been investigated. The simulation results have shown the rapidity and accuracy of the proposed method.