  A complex Al/Cu magnetic pulse welding interface is systematically
investigated using experimental characterizations and numerical simulations. A
Coupled electromagnetic-mechanical simulation is proposed to compute the impact
velocity and impact angle along the entire interface. This model allows to
further understand the formation mechanism of various interface characteristics
during MPW. The results revealed that the impact velocity gradually decreases
in conjunction with the gradual increase of the impact angle. These simulations
elucidate the experimentally observed successive interface morphologies, i.e.,
the unwelded zone, vortex zone, intermediate (IM) layers and wavy interface.
Microstructural characterizations show that the IM layers are formed by
mechanical mixing combined with melting and are characterized by highly
heterogeneous porous zone with random sizes and distributions of void.
Subsequently, an Eulerian simulation is proposed to investigate the
thermomechanical effects during the wave formation which vastly influence the
joint quality. The predicted wavy morphologies, temperature distribution and
average equivalent plastic strain along the interface provided a better
understanding on the formation steps of the experimentally observed wave
morphologies. The actual kinematics during wave generation revealed that the
wave was formed with repeated deformation of the interface material. The wave
amplitude increases with increasing jetting angle; while the wavelength
increases with increasing collision point velocity.
