Electromagnetic attraction bulging of small aluminum alloy tube based on a field shaper

Abstract

Electromagnetic forming (EMF) is a technology that uses Lorentz force to drive the deformation of light alloy. In the processing of small metal pipe fittings, attraction forming is beneficial to reduce the design requirements of forming coils and the application cost of actual tooling. However, the attractive dual-frequency current method requires strict matching between currents. This will lead to difficulty in controlling and changing the attractive force, thus reducing the uniformity of the deformation of the workpiece. To solve this problem, a field shaper is introduced to optimize the distribution of electromagnetic force and improve the uniformity of pipe forming. The finite element model including circuit field, electromagnetic field, and structure field was established, and the bulging of an aluminum alloy pipe fitting with a radius of 10 mm and a length of 40 mm under the action of 9-kV power supply was simulated. The results show that the deformation uniformity is increased by 15% and the degree of shape change is increased by 8.9% with the addition of field shaper. It is proved that field shaper can improve the uniformity of pipe fitting.