Effect of static magnetic field and cold wire feeding on the mechanical properties of stainless steel/nickel-based functionally graded material fabricated by wire arc additive manufacturing

Abstract

A 316L stainless steel/Inconel 625 functionally graded material was fabricated by gas metal arc-based wire arc additive manufacturing assisted by a static magnetic field and external cold wire feeding. The effects of magnetic field assistance on surface morphology, microstructure, and mechanical properties were investigated. The observed improvements are consistent with enhanced molten pool convection induced by the magnetic field, resulting in refined grain morphology and reduced elemental segregation. Compared with the non-magnetic condition, the magnetic-assisted sample exhibited higher hardness, approximately 10% higher tensile strength, and 19% higher yield strength, while maintaining comparable ductility. These results indicate that the combined application of a static magnetic field and cold wire feeding improves structural homogeneity and mechanical performance of WAAM-fabricated functionally graded materials.