# Research on Nondestructive Testing Method Based on Magnetic Characteristics of Electron Beam Weld Defects

## TL;DR

This paper introduces a new nondestructive testing method using magnetic characteristics to detect defects in electron beam welds of aluminum alloys.

## Contribution

The novel contribution is a weak magnetic NDT method based on the geomagnetic field for detecting weld defects in aluminum alloys.

## Key findings

- A simulation model was developed to study magnetic field distribution around weld defects.
- Wavelet transform and least squares method effectively identified magnetic anomalies at cracks.
- Experimental results confirmed the method's safety, speed, and accuracy in defect detection.

## Abstract

In view of the problems of poor safety, slow detection speed, and low accuracy of existing nondestructive 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 combining the wavelet transform and the 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.