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.