Automotive Stamping Cae Technology And Its Industrial Application

Using the opportunity of the new product N1 in the SAIC GM Wu Ling Automotive LTD. Corporation,the CAE technique and its industry application researches of sheet metal forming for automotive body panels have been investigated in this paper, the main conclusions are as follows:1 The optimal gap value between the die and the punch is 15% of the thickness for the blank.2 The stamping results can't be improved evidently by the partial improvement of the blank shape.3 The influence of the stamping results from the variety of friction coefficient between the blank and the die is much less than that from between blank and punch or between blank and binder. ( i.e., the so-called stick mold property won't benefit for stamping for the forming of complicated automotive body panels)4 If springback analysis is not necessary, the Belytschko- Tsay shell formula with 3-ponts integral in normal direction can be used. Otherwise, the shell formula with 5-ponts integral in normal direction is preference, and the full rank integral shell formula is the best selection.5 For the stamping condition is worse, the blank possible to or be about to be cracked but the crack degree is not special serious, using the Barlat's 3-parameter plasticity material model can acquire the dependable results, and the compute expenses have no obvious difference compared with that of using the transversely anisotropic elastic-plastic material model.6 Only the forming situation that drawbeads arrange mainly with long straight line, the force-function can be used to simulate the function of drawbeads correctly, otherwise, the finite element mesh model of drawbeads is preference.7 Using the finite element mesh model of drawbeads, the number of elements will increase significantly, but the augmentative calculation expense is very low. At the same time, although there are serious distortion problem in blank elements under the drawbeads that will increase the error of the calculation results, the calculation error from adopting force-function model of drawbeads is much more. Therefore, it is suggest that we shouldn't adopt the force-function model in the CAE for the forming of complicated automotive body panels.8 Owing to the element size in the tool do not participate in deciding the critical time-step that decided from the Courant stability condition, so that the demand for the mesh of the tool is only need to fit to imitate the shape of the tool surface.