Investigations on remote laser beam welding of dissimilar joints of austenitic chromium-nickel steel (X5CrNi18-10) and aluminum alloy (AA6082-T6) for battery housings

Owing to the enormous potential of weight saving and the consequential reduction of pollutant emissions, the use of hybrid components made of steel and aluminum alloys is increasing steadily, particularly concerning automotive lightweight construction. Especially in the automotive industry, remote laser beam welding has been established as a suitable and efficient method for joining similar material for several years. In contrast to this, thermal joining of steel and aluminum alloys involves different metallurgical and technological challenges, due to the formation of hard and brittle intermetallic phases, which decrease the strength and the formability of the dissimilar joints. In this context, the results presented show investigations on remote laser beam welding for dissimilar lap joints of the austenitic chromium–nickel steel material X5CrNi18-10 and the precipitation hardening aluminum wrought alloy AA6082-T6. For example, lightweight battery housings for electromobility are potential applications for this technology. Among other things, the influence of the energy per unit length (welding speed) and the number of welding seams on the achievable strengths are analyzed. Characterization of the dissimilar joints includes the use of tensile shear tests, metallographic analyses, hardness tests, and elemental analyses, depending on the energy per unit length.