| In recent years, the rapid development of automobile industry has brought increasingly serious environmental and energy issues. In order to effectively reduce pollution and energy consumption, light weight materials and structures become the main trend of modern structural design. The lightweight metal material like aluminum has been used widely in the advanced manufacturing field. However, there are many problems during the aluminum alloy forming process, such as it is difficult to control material flow, the plate's stress and strain are distributed unevenly, springback and the forming precision is difficult to control, and so on. Therefore, the forming quality has become a major obstacle for aluminum alloy sheet be used inElectromagnetic forming (EMF) is a kind of high velocity forming technique, this can accelerate the sheet to velocities on the order of 200 m.s-1 over a distance of a few millimeters. This high velocity forming can be quite beneficial.It can improve formability and strain distribution, reduce the springback of the aluminum alloys. Compared with the traditional springback controlling methods, EMF make the curved workpiece be calibrated by fitting to the female die, through adjusting the electromagnetic force to remove springback, it is easier to decrease the springback via this method.In this paper, finite element analysis software ANSYS is used to discuss the surface coil's magnetic field of electromagnetic properties. Simulate the discharge circuit and find the variation that the current of surface coil changes with the time; Simulate the magnetic field of the surface coil's electromagnetic forming and find the distribution of magnetic field and magnetic field strength of the surface coil.Magnetic deformation process of sheet material surface parts simulated with the FEA software Dynaform. The result indicates that:1)The forming effect is decided by the spacing between the sheet and die. The results show that the distance between sheet metal and die increases, the deformation of the workpiece after forming reduces and springback increases.2)With the increase of discharge energy, the magnetic pressure acting on the sheet metal surface increases, and the posts modular is better.3)Formed under the same energy, the forming quality of thick sheets is better than the thin ones. With the increase of slab thickness, the workpiece's deformation increases and the springback decreases after sizing. To take full advantage of the magnetic field strength to produce the maximum deformation of sheet metal, we should select appropriate discharge frequency under the sheet thickness, to control that the skin depth is equal to the thickness of sheet, and the forming effect will be better.4)Using electromagnetic forming technology for forming or sizing sheet can control the springback, wrinkling and other defects in metal forming effectively, electromagnetic forming process has important practical significance. |
