Quantitative Analysis of Anisotropic Magnetic Memory Signals of Wire and Arc Additively Manufactured Low Carbon Steel

In this paper, the anisotropic magnetic memory signals of wire and arc additively manufactured (WAAM) low carbon steel is investigated and quantitatively analyzed by tensile test. Five specimens (200 × 40 × 4 mm) with different print directions (0°, 30°, 45°, 60°, 90°) were extracted from the WAAM rectangular tubes for testing under tensile loads up to 60 kN. The residual magnetic field (RMF) on the surface of the specimens was measured using a TSC-PC-16 magnetometer. The distribution and evolution of RMF signals were presented and quantitatively analyzed. The findings demonstrate a clear anisotropic behavior in the tangential RMF responses, with orientation-dependent sensitivity to stress, while the normal component is less sensitive to material orientation. The correlation between magnetic memory parameters and the applied load was revealed. The linear relationship between the characteristic magnetic memory parameter and the printing angle has been established. There is a certain correlation between the RMF gradient signals and the surface morphology of materials, which can be used to characterize the roughness of additive parts. The results suggest that magnetic memory techniques show potential for non-destructive evaluation of WAAM-produced steel components, providing insights into stress distribution. These findings contribute to the advancement of quality control measures in additive manufacturing, promoting safer applications in critical structural environments.