Comparison of the deformation behavior of circular hole-flanging obtained by electromagnetic forming and stamping

In this paper, the deformation behavior of circular hole-flanging obtained by electromagnetic forming (EMF) and stamping is investigated. Numerical simulations are performed to analyze the deformation of the 5052 aluminum alloy sheet and the stress–strain characteristics obtained by the two forming processes. The correctness of the simulation results is verified experimentally. It has been found that with the increase of the discharge voltage, the sheet flanging area gradually changes from an inclined plane to a vertical plane. The sheet deformation is not synchronous due to the uneven electromagnetic force distribution, while four special nodes collide with the die successively at a discharge voltage of 9 kV. The maximum contact error by EMF at 9 kV is less than 0.3 mm. The forming accuracy obtained by stamping is poor. The maximum gap between the sheet and mold is 1.1 mm when the punch diameter is equal to 75.2 mm. After both electromagnetic flanging and stamping, the maximum principal strain appears at the sheet edge region, which is prone to rupture.