Universal Uniform Pressure Tooling Coil-A Dual Mode Pulse Forming Tooling Coil for Metallic Sheets

Electromagnetic repulsive forming technology is a high-strain rate forming technology used for shaping of components made of metallic sheet, tube forming, joining operations, explosive welding, etc. A current pulse is passed through the tooling coil, generating a high-intensity magnetic field, which interacts with the induced currents in the electrically conductive workpiece, resulting in significant plastic deformation. The generated magnetic pressure, in this case, pushes the workpiece away from the coil. Electromagnetic attractive forming technology is another method to produce an attractive force on the workpiece using induced currents. However, this requires specialized pulsed power circuits and tooling systems to achieve the final objectives. This paper presents the design of a novel uniform pressure universal tooling coil that can be used for both repulsive and attractive forming of the workpiece without changing the pulsed power source and the tooling coil configurations. The designed tooling coil provides flexibility of operation, and the forming modes can be easily switched as per the process requirements. The paper focuses on the electromagnetic design of the tooling coil, and the performance of the tooling coil has been simulated in both configurations. The operating principle has been described in detail, and the results have been discussed in both the forming modes.