Joining aluminium with copper is one of the current challenges regarding electro mobility. However, the joining of both metals by conventional fusion welding is difficult because of poor weldability arising from different chemical, mechanical and thermal properties of the materials and especially from the massive formation of hard and brittle intermetallic compounds (IMC) weld interface. In order to accomplish the difficult task of joining aluminium and copper several new joining technologies and strategies such as Laser Beam Welding (LBW) using highly dynamic beam deflection, Friction Stir Welding (FSW), Laser Induction Roll Plating and Electromagnetic Pulse Welding (EMPW) were investigated.
The current contribution focuses on different technological approaches to master the task of joining aluminium and copper. Thereby, the different joining technologies are compared with respect to process efficiency and weld quality. Special consideration is given to the study of interface morphology and microstructure of the welding zone by means of SEM and TEM. Comparing the different joining technologies, all of them are basically suited to realize a dissimilar metal joint consisting of aluminium and copper plates with reproducible bond quality. The formation of an intermetallic seam cannot be completely prevented, however its size can be controlled by optimising process parameters and joint geometry. Comparing the technologies regarding the size of intermetallic seam LBW produces the largest seam (< 20 m) whereas both FSW and LIRP allows to reduce the seam size in the sub-micrometre range.