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High-velocity electromagnetic sheet-metal forming and processing has many potential advantages over more conventional techniques, including: higher-forming limits, resistance to wrinkling and springback, one-sided tooling, and physical contact to only one side of the work piece. Traditional electromagnetic actuators are flat spirals that produce a nonuniform pressure distribution, limiting the types of parts that can be formed. A new type of electromagnetic actuator, the uniform pressure (UP) actuator, has been developed. The UP actuator can uniformly and efficiently accelerate conductive sheet metal to velocities on the order of 200 m/s or greater over distances of a few millimeters. When the material is arrested by impact with a tool, high-forming pressures can be imparted to it. The utility of the UP actuator is illustrated here by demonstrating its ability to form sheet metal components with intricate shape, to shock harden, and also to pick up nearly arbitrarily small details from a die surface. Thus, electromagnetic processing with the use of the UP actuator offers the unprecedented ability to simultaneously form and engineer the surface morphology and microstructure of sheet metal samples.

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This paper investigated the effect of magnetic pulse welding (MPW) condition (welding power, surface scratches, and contamination) on the establishment of welding between aluminum and copper tubes, and the associated welding mechanisms. The results showed that higher applied power and surface scratches in tangential direction were in favor for good weld, and oil on the surface prevented welding. Direct evidences were obtained on local interface melting under a high welding power. CuAl intermetallics with different atomic ratios were identified by energy dispersion spectrum (EDS) chemical analysis and by microscratching test. The mechanisms of MPW and the process improvement were discussed.

Hemming is usually the last stage of production for automotive closures, and therefore has a critical effect on the quality of the final assemblies. The insufficient formability of aluminum alloys creates a considerable problem in the hemming process. To address this issue, electromagnetic forming was utilized to hem aluminum alloy sheets. Electromagnetic forming is a high strain rate forming process that is currently being investigated by both academia and industry. Past studies have shown that the formability of metals can be significantly improved during electromagnetic forming, which benefits the hemming of aluminum alloys. This article presents the experimental results of hemming Al 6061-T6 sheets using electromagnetic forming. The effects of the parameters of electromagnetic hemming on the hem quality are discussed. In addition, the numerical simulation results of electromagnetic hemming are presented to enhance the understanding of the process and to determine the efficacy on an industrial scale.