Electromagnetic Pulse Welding of Tubular Products: Influence of Process Parameters and Workpiece Geometry on the Joint Characteristics and Investigation of Suitable Support Systems for the Target Tube

In this experimental research, copper to steel tubular joints were produced by electromagnetic pulse welding. In a first phase, non-supported target tubes were used in order to investigate the influence of the workpiece geometry on the weld formation and joint characteristics. For this purpose, different joint configurations were used, more specific the tube-to-rod and the tube-to-tube configurations, with target workpieces with different diameters and wall thicknesses. Also, some preliminary investigations were performed to examine a support method for the target tubes. In a second phase, suitable support systems for the target tubes were identified. The resulting welds were evaluated in terms of their leak tightness, weld length and deformation of the target tube. It can be concluded that polyurethane (PU), polymethylmethacrylaat (PMMA), polyamide (PA6.6) and steel rods can be considered as valuable internal supports leading to high-quality welds and a sufficient cross-sectional area after welding. Welds with a steel bar support exhibit the highest cross-sectional area after welding, but at the same time the obtained weld quality is lower compared to welds with a PA6.6 or PMMA support. In contrast, welds with a PA6.6 or PU support show the highest weld quality, but also have a lower cross-sectional area after welding compared to steel internal supports.