Finite element model-based approach for magnetic flux leakage testing of steel plates using 2D tandem GMR array sensors

This paper proposes a finite element (FE) model-based approach to the magnetic flux leakage (MFL) technique for enhanced detection and fast imaging of defects in ferromagnetic steel plates using 2D tandem giant magnetoresistive (GMR) array sensors. The approach is based on the selection of the best magnetising structure and optimisation of the parameters of the magnetisation unit, followed by optimisation of the location of GMR array sensors. The approach is evaluated experimentally for the detection of surface and sub-surface defects in 5 mmand 12 mm-thick carbon steel plates. Studies reveal that the approach is effective for enhanced detection and fast imaging of defects, without the need for extensive physical testing. The study also reveals that the detection sensitivity of the MFL technique is influenced by the thickness of the steel plates.