Laser roll welding of dissimilar metal joint of zinc coated steel and aluminum alloy

There is a subject to reduce the weight of car body by aluminum alloys replace steel as some structural body parts for improving fuel consumption and CO₂ generation. As one of the solutions, the multi material car body concept using aluminum alloys and high strength steels is discussed recently. Therefore, new welding processes by which these dissimilar materials can be joined in high reliability and productivity are demanded. Laser Roll Welding was developed for joining of dissimilar metals by M.Kutsuna and M.Rathod in 2002. In the present work, Laser Roll Welding of zinc coated steel and aluminum alloy was investigated, and the process parameters were studied. Otherwise, the influences of process parameters on the weldability, the formation of intermetallic compound layer and the mechanical properties have been investigated. When intermetallic compound layer thickness was less than 10 µm, failure of tensile-shear test specimen occured in the base metal of the zinc coated steel.