Additive manufacturing of steel-bronze bimetal by shaped metal deposition: interface characteristics and tensile properties

In this paper, mild steel-silicon bronze bimetal based on the single-pass multi-layer model was fabricated by shaped metal deposition utilizing gas metal arc welding technology. Suitable deposition parameters of silicon bronze were chosen to match the specific size of mild steel wall. Then the characteristics of interface were analyzed. The results show that Cu element did not exist on the steel side, but Fe element entered the bronze side in the forms of particles and big chunks. Meanwhile, owing to the physical and chemical reasons, the silicon element concentrated in the intermixing zone and on the bronze side where Fe element appeared. The interface between steel and bronze had good adhesion without cracks or pores, and metallurgical bonding was achieved. The tensile strength of the bimetal reached 305 MPa and fracture occurred near the middle of bronze side, implying a firm connection between steel and bronze was obtained.