Finite Element Simulation and Experiment for Electromagnetic Flanging Forming of Aluminum Alloy Sheet.

Abstract

In order to address the problem of the large gap in the film on the straight edge of the electromagnetic flanging forming by the flat coil affecting the quality of the flanging part, a multi-layer variable-turn stepped coil is proposed. Numerical simulation analysis and experimental research were conducted on the electromagnetic flanging forming process of flat coil and stepped coil. Research shows that in the early stage of forming, the electromagnetic force of the flat coil is uniformly distributed at the edge of the hole and the middle of the deformation zone of the sheet metal, causing the upper surface of the middle of the deformation zone of the sheet metal to present radial compressive stress and tangential compressive stress, and the upper surface of the sheet metal at the fillet of the die to present radial tensile strain, tangential compressive strain and thickness direction compressive strain. The electromagnetic force of the step coil is mainly concentrated at the hole edge of the sheet metal, causing the upper surface in the middle of the deformation zone of the sheet metal to present radial tensile stress and tangential tensile stress, as well as radial tensile strain, tangential and thickness direction compressive strain. Under the flat coil, the sheet material mainly undergoes plastic deformation under the action of axial electromagnetic force and can only be bent into a curved edge. Under the stepped coil, the sheet metal undergoes plastic deformation simultaneously under the combined action of axial and radial electromagnetic forces and can be flipped into a vertical edge. The feasibility of the electromagnetic flanging forming of the stepped coil was verified through experiments, and the experimental results were basically consistent with the simulation results.