Effects of process parameters on mechanical performance and interfacial morphology of electromagnetic pulse welded joints between aluminum and galvanized steel

Magnetic pulse welding (MPW) exhibits an enormous advantage on welded joints of dissimilar metals. Various process parameters (discharge energy and standoff distance) were considered to weld aluminum alloys and galvanized steels by MPW. Mechanical behavior and interfacial morphology of MPW joints between galvanized steels and aluminum alloys were investigated systematically. Results indicated that the weldable standoff distance range of the MPW joints was enhanced with ascending discharge energy. The change of weld dimension (width and gap of the effective weld) was the main reason for the difference in joint performance at the various welding process parameters. With enhancing discharge energy, both the length of zinc-free zone and the size of interfacial waves increased, which contributed to the enhancement of the mechanical strength of the MPW joint. With increasing standoff distance, the strength of MPW joints appeared to increase first and then decrease. This was owing to the change of interfacial wave size and zinc-free zone length.