Assessment of joint configuration and welding parameters for the dissimilar joining of AISI 304L and AISI 410S stainless steels by the friction stir welding

Abstract The FSW process parameters for dissimilar welding of AISI 410S and 304L steels were varied to provide a combination of good surface finish, no voids, and complete tool penetration. These findings have practical implications, as they can guide the welding industry in achieving optimal results. Preliminary tests were performed to analyse the proper position of the steels between the advancing and retreating sides. In welding, axial forces from 25 to 40 kN were applied, keeping the rotational speed constant at 450 rpm and the welding speed at 1 mm/s. Due to the differences between the physical and chemical properties of welded steels, a reduction in flash production and void formation along the stir zone is observed with the positioning of ferritic stainless steel AISI 410S on the advancing side. As the axial force increases, there is an increase in flash production, being more intense on the advancing side than on the retreating side. However, this increase in axial force decreases the material insertions' size and nullifies the joints' root flaws. It is possible to produce dissimilar joints between AISI 410S / 304L steels by the FSW process with a good surface finish and no defects in the stir zone.