Research on nondestructive testing method based on magnetic characteristics of electron beam weld defects

In view of the problems of poor safety, slow detection speed and low accuracy of existing non-destructive testing (NDT) technologies such as X-ray methods and ultrasonic detection in detecting electron beam weld defects in aluminum alloys, this study proposes a weak magnetic NDT method based on the geomagnetic field. Firstly, the finite element analysis method was used to establish a simulation model of aluminum alloy electron beam welding defects, and the distribution characteristics of the magnetic field around weld defects such as cracks and pores were obtained. Then, the magnetic anomaly signal at the crack weld was identified by the combination of wavelet transform and least squares method. Finally, experimental tests show that the proposed method can safely, quickly and accurately detect the defects of aluminum alloy electron beam welds.