The Stamping Simulation And Springback Analysis Of Front Bulkhead

The complexity of the deforming rules during the stamping process, which made it difficult to be analyzed, is caused by those characters of auto-body panel, such as the complicated shape, the big-sized structure, strict request for the surface and so on.In recent years, with the development of the auto industry, auto-body forming and mould design becomes the key technology in our national mould field. To develop high efficiency, high quality product with low cost is what all the providers strive for. The appliance of CAE technology could predict the defects of fracture, crinkle and springback by simulating the flow of the material during the stamping process. The main contents are as follows:1. The theory of dynamics explicit algorithms for auto-body panel stamping analysis was elaborated and researched as follows: increment movement equation's expression and formation of solution application, finite element equation, relation of strain and stress, element theory, centre differences theory and its numerical stabilization, the selection of element formulation, mesh division, contact and hourglass processing, friction treatment.2. The structure and forming character of the automobile panel was introduced, as well as the influence to the forming caused by commonly used stamping materials and the performance of these materials. The usual defects in stamping, root cause and the general solution were analyzed. Some finite element analysis software used for simulating the stamping were introduced, especially focused on DYNAFORM which used in this paper. The general steps of plate shaping finite element analysis were concluded. Critical technologies of panel stamping numerical simulation were summarized.3. The finite element model of front bulkhead was built and the forming parameter was set to simulate the stamping forming. After analyzing the problems of stamping process, the optimal process parameters were determined by optimization of blank holder forces and drawbeads. The best result of stamping process was obtained when blank holding force is 700KN and height of drawbead is 6 mm.The actual production and the results of simulations is identical very much.4. The principle of springback was analyzed. The factors influenced springback was introduced, as well as the research of simulation methods and algorithm of springback. The parameters of springback simulation were confirmed. Unloading springback to the components and edge trim springback were analyzed.The maximal springback does not exceed 2mm,it have positive guidance value to mold design.CAE technology during the production exactly simulated the whole plate stamping process, which accurately predicted the possible defects of the plate during the forming; hence the stamping technology scheme could be modified in time before the tooling manufacturing. The stamping technology and quality of tooling design were improved by verifying the simulation calculation. The high-quality mould would be obtained with little modification and test. The development cost was reduced and the development cycle of tooling design was shortened.