Study of a Topology for Plate Electromagnetic Forming Based on Inner Reverse and Outer Positive Double Coil Loading

Abstract

While electromagnetic forming is widely used for aluminum alloy materials, the nonuniformity of plate radial deformation is still a key issue that restricts the wide development of this technology. This paper presents a new electromagnetic-forming topology. The proposed topology comprises outer ring double-coil plates along with an inner loop driving coil of a small number of turns whose geometrical parameters are optimized to adjust the induced eddy current of the plate. Numerical simulation results show that the presence of an inner ring driving coil shapes the magnetic field in a manner that the radial electromagnetic force is concentrated close to the edge of the die which affects the center of the plate. With optimum design for the geometrical parameters of the proposed inner ring driving coil, the electromagnetic force distribution can be adjusted over the plate, resulting in an improved plate deformation with an increase in the maximum uniform deformation area from 24mm to 65mm. Results also show that the proposed inner and outer ring double coil loading method possesses superior advantages over the traditional flat spiral coil loading method.

Research on Electromagnetic Force Distribution and Deformation Uniformity of Tube Electromagnetic Bulging Based on Concave Magnetic Field Shaper

“…However, due to the end effect of this structure of forming coil the radial electromagnetic force exerting on the middle section of the tube is much larger than that at both ends which results in poor tube uniformity in the axial direction [7]. A tube electromagnetic bulging method using a concave driving coil is proposed in [8] to realize uniform tube radial deformation by weakening the electromagnetic force in the middle of the tube.…”