Deformation Behavior of Aluminum Alloy Plate Under Electromagnetic Force Assisted Line-Heating Process

As a new technique for the deformation of aluminum alloy plate with complex curved surface which is used in shipbuilding, electromagnetic force assisted line-heating process, or EFALH for short, can promote forming efficiency and produce anticipated curved surface within the range of temperatures required in production. For a start, the process unit and experimental scheme for EFALH were introduced in the article. After the experiment, it was confirmed that the electromagnetic force do have auxiliary effect on the deformation of aluminum alloy plate. Then, for the EFALH process, three-dimensional numerical simulation was performed, and the simulated results were verified by experimental data. Influence on the deformation process caused by the difference in the time and current amplitude of electromagnetic force was studied through numerical simulation. At last, the deformation behavior of the plate under EFALH process has been analyzed from two perspectives, namely the periodism of pulsed electromagnetic force and the loading and unloading procedure in the load cycle caused by electromagnetic force. Nowadays, aluminum alloy plate has been applied more and more extensively in shipbuilding, due to its advantages such as lower density, higher strength, higher stiffness, better corrosion resistance, and excellent welding performance than the traditional steel plates (Wang 1994; Biao 2005; He 2005). It is of great significance to find out an appropriate forming method for the production of double-curved aluminum alloy plates installed at hull stem and stern. At present, there are mainly two forming methods, namely cold forming technology and thermoforming technology.