Research On The Complex Structure Parts By HydroAdynamic Deep Drawing Based On Numerical Simulation

With the development of technology and people's living standard increasing day by day, people's requirements are increasingly strict for all the various performance indicators of product, especially for the parts which are difficult to product. The traditional stamping form can easily result in winkle and damage, etc. and surface quality is difficult to meet the demands of the people. Hydraumatic deep drawing is complying with the demand of the development and growing a kind of advanced soft mould forming technology. Because of the advantages of the high precision of production, good surface quality, high limit drawing ratio, it quickly gets the wide attention of scholars at home and abroad.Precisely in response to this research trend, and in order to overcome the appearance of crack, drawing deficiency of the complex structure parts, this paper focuses on the finite element simulation study of hydraumatic deep drawing of stepped geometries part and automobile front fender by using professional metal forming simulation software Dynaform5.7.1. Applying the forming cloud and wall thickness distribution of part as evaluation criteria, selecting reasonable parameters and revealing the influence of changes in process parameters on parts thereby enhance wall thickness uniformity and film degree of the stepped geometries part and the front fender, and so on.Secondly, the forming of stepped geometries part is analyzed. Because there are a several fillet in stepped geometries part and sheet deformation is difficult, the traditional deep drawing process can hardly form in one time. In this paper, simulation study indicates that selecting the appropriate process parameters is beneficial to improve the formability of sheet for different part models. The final reasonable process parameters are: chamber pressure is 55 MPa, the punch velocity is 5000 mm/s, the blank-hold gap is 1.10 mm and the friction factor is 0.04.Finally, combined with the simulation process and results of the step part, the hydraumatic deep draw process of automobile front fender which is more complex is studied by using finite element simulation. The results show that because of the complexity of the shape of the front fender and highly inconsistent forming, the setting of drawbead on the fender forming performance has important influence. A reasonable drawbead resistance coefficient can adjust flow uniformity of sheet. Through summarizing a series of simulations, the final reasonable process parameters are: the loading way of chamber pressure is the second way, the punch velocity is 5000 mm/s, the blank holder press is 100 t and the friction coefficients is 0.04 and 0.14.