Production of low-volume aviation components using disposable electromagnetic actuators

Electromagnetic forming is commonly used to produce high strain rates to improve the formability of sheet metal. The objective of this paper is to discuss the feasibility of the use of disposable actuators during electromagnetic forming of two aluminum components: a very simple part with a one-dimensional curve, and a realistic part whose main feature is a convex flange with two joggles. The main forming complications after the parts were formed using conventional methods were the presence of wrinkles and excessive springback. The goal of this work is to use large controlled electromagnetic impulses to minimize the springback of these components from a rough-formed shape. The optimum test protocols for electromagnetic calibration of the components were determined by optimizing parameters such as actuator design, tool material, press force, and capacitor discharge energy. The use of disposable actuators for electromagnetic calibration of the parts showed significant reductions in springback compared to the parts which were only preformed using conventional techniques (hydroforming and rubber pad forming). Springback was decreased in the curved component by up to 87%. The wrinkles were eliminated on the flanged component, the joggles were formed properly, and the average bending angle of the part was improved from 95.3° to 90.3°, very near the target bending angle of 90°. This study demonstrates that these techniques can be used to improve current sheet metal production processes.