Within the last years there was a rising interest in dissimilar metal combinations. The main goal of these developments are weight reduction, properties optimization or the tailoring of properties for specific applications.
The joining of dissimilar metals such as aluminum to steel and aluminum to titanium can be realized by laser welding due to a very localized energy input of the welding source. Localized energy input leads to a controlled heat distribution and to a minimized interaction of the joined materials. Comparable to conventional thermal joining technologies, intermetallic phases are formed during the joining process. These intermetallic phases have a size and a composition dependent influence on the properties of the joints. Due to locally restricted energy input, high joining speed and accompanying high cooling rates laser beam welding prevents an excessive formation of intermetallic phases. The formation of intermetallic layers can be limited to a size below 10 µm which leads to desirable mechanical properties including higher ductility of the joint.
Within this paper the phase formation in Al/Fe-joints is described. The characterization was carried out by trans- and scanning electron microscopy. Additionally, the mechanical properties of Ti/Al and Fe/Al-joints are presented. Finally, potentials for industrial application for dissimilar metal combinations are given.