Effects of the inner/outer diameters of flat spiral coils on electromagnetic sheet metal formation

摘要

The inner and outer diameters are two of the most fundamental geometry parameters of flat spiral coils in electromagnetic sheet metal forming systems that govern the spatial distribution of the produced forming force and thus determine the deformation behavior of the sheet metal workpiece. Aiming to provide a guide for coil design, this paper experimentally and numerically investigates the effects of these two parameters on the final deformation morphology of the electromagnetically formed workpiece in terms of the forming shape, dome height, draw-in, and thickness distribution. Moreover, the dynamic process under various diameters is numerically analyzed to reveal the underlying mechanism. The results show that the change in the inner/outer diameter of the coil directly alters the action region and uniformity of the Lorentz force on the workpiece, which induces different forming velocity fields and forming processes, thus changing the morphology of the final deformed parts. The investigation provides a reference for the design of flat spiral coils for electromagnetic sheet metal formation.