Influence of aluminum coating and diffusion affecting additives on dissimilar laser joining of steel and aluminum

Steel as well as aluminum play an essential role for multi-material construction in the field of lightweight design. However, the thermal metallurgical joining of these materials is difficult due to their different physical properties and the formation of intermetallic phases. This paper describes investigations on laser joining of aluminum plated steel with aluminum. Furthermore examinations with additives acting as diffusion barriers were carried out. The results indicate that the aluminum coating is advantageous for the joint. The growth of intermetallic phases can be reduced by application of carbon and tungsten to the steel sheet tip. (C) 2013 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of the German Scientific Laser Society (WLT e.V.)