Microstructure evolution of a dissimilar junction interface between an Al sheet and a Ni-coated Cu sheet joined by magnetic pulse welding

摘要: Abstract An Al sheet and a Ni-coated Cu were lap joined by using magnetic pulse welding (MPW). Tensile tests performed on the sheets, good joint was achieved at discharge energy of > 0.9 kJ. The weld interface exhibited wavy morphology an intermediate layer along interface. Microstructure observations revealed that Ni coating region consisted Ni–Al binary amorphous alloy contained very fine nanograins. fragments indicative unmelted residual from also observed in parts layer. Formation these features can be attributed to localize melting subsequent high rate cooling molten confined during MPW process. In absence oxide film, atomic-scale bonding between surfaces after collision. utilises impact energy, which affects surfaces. From obtained results, is increased contact area, anchor effect, work hardening, suppressed formation intermetallic compounds