Electromagnetic Springback Reshaping

Abstract

Electromagnetic forming is an impulse-based forming technique where high dynamic pressure is distributed to conductive materials by pure electromagnetic interaction. The aim of this paper is to present how springback can be controlled when the EMF technique is used as a second corrective step; bringing formed parts to the desired final shape by means of magnetic impulses in critical areas of the formed components. This analysis is based on the results of two experimental studies. In the first, the selected preformed specimen shape is the L-shape bent part of HSS DP600, in 0.8 and 1.95 mm thickness, and Aluminium Alloy 5754, in 1 and 2 mm thickness. The second geometries are two rocket nozzle panels made of a thick but soft copper alloy. While the geometry and the material are the similar, the first approach of this work was developed using smaller panels (about 30 cm long) and the full size (about 1 m long), in order to study the behaviour of the material and the approximate energy levels required to scale up the full size panels. Overall this study shows EM forming can have a potent effect in controlling springback.