Interfacial Morphology of Magnetic Pulse Welded Aluminum/Aluminum and Copper/Copper Lap Joints

Abstract

In order to investigate interfacial morphology and their welding condition dependency, Al/Al and Cu/Cu lap joints were fabricated by magnetic pulse welding under various discharge energies. A part of flyer plate along the longitudinal direction of the coil bulged toward a parent plate and hit the parent plate. Two parallel seam-welded areas were formed along the side edges of coil, but the area between them was left unwelded. The welding interface exhibited characteristic wavy morphology, which was similar to that of explosive welding. Wavelength and amplitude of the interfacial wave were not uniform, but gradually changed through the interface. In addition, the maximum wavelength and amplitude increased with increasing discharge energy. Both macro-and microscopic features of interfacial morphology are considered to be due to the oblique collision behavior between the plates, in which traveling velocity, collision angle and collision pressure of the plates gradually change during the welding for a few microseconds.

High-Speed Deformation and Collision Behavior of Pure Aluminum Plates in Magnetic Pulse Welding

“…The initial gap distance between them was fixed to be 3 mm, which was larger than that of the experimental condition in the previous works. [1][2][3] The larger gap distance is of help to detect high-speed deformation and collision behavior clearly. The discharge energy was 2.5 kJ.…”

“…The present authors did the magnetic pulse welding of the Al/Al lap joint under the conditions that the initial gap distance of 1.0 mm. 1,3) The collision velocity was examined for the discharge energy ranging from 0.5 to 4.0 kJ. 3) In order to obtain the collision velocity, the duration time, t, from the onset of discharging to the collision of the plates was measured by using electrical signals.…”

“…1,3) The collision velocity was examined for the discharge energy ranging from 0.5 to 4.0 kJ. 3) In order to obtain the collision velocity, the duration time, t, from the onset of discharging to the collision of the plates was measured by using electrical signals. The collision velocity was calculated by l=t, where l is the initial gap distance between two plates.…”

“…[1][2][3] A part of the flyer plate along the longitudinal direction of the coil bulged toward a parent plate and hit the plate with a high speed. Welding was achieved in two parallel areas along the coil, and no welding took place in the area between them ( Fig.…”

Fabrication of 2000 Series Aluminum Alloy Lap Joint Sheets by Magnetic Pulse Welding and Their Interfacial Microstructure Observations

“…[18][19][20][21][22][23] Joining for practical materials have also been attempted, such as the joining of 6000 series aluminum alloy and SPCC where good bonding is achieved, and the details on the structure of the bonding interface have been reported. 24) However, in MPW, there are many reports on similar joining of pure metals.…”