Enhanced Acoustic Emission Detection Induced by Electromagnetic Stimulation With External Magnetic Field

This paper introduces a new electromagnetically induced acoustic emission technology (EMAE) enhanced by an external magnetic field. The external magnetic field generated by Nd-Fe-B magnet can improve the ability of detecting the defects, due to the even bigger deformation generated by the enhanced Lorentz Force. In this paper, the finite-element model of EMAE including an external magnetic field has been implemented in accordance with the practical experiment models. The sample's deformation has been analyzed when the exciting coil locates at different positions. The experiment of EMAE is built according to the finite-element analysis (FEA) results. Experiments' outcomes indicate that the defect itself can generate modulated acoustic emission signals, which could be used to boost the detection ability of small cracks in the thin-walled metallic structures.