NUMERICAL ANALYSIS OF THE DEEP DRAWING PROCESS INCLUDING THE HISTORY OF STRESS AND STRAIN

摘要

This paper discusses the results of a numerical study of circular cup drawing of steel sheets using finite element method. The drawing process is considered as a geometrical and physical nonlinear problem with unknown boundary conditions in the contact area of the system, such as the tool and the workpiece. The updated Lagrangian description is used to characterize these nonlinear phenomena on a typical incremental step time. Numerical results are obtained using an explicit method in Ansys/Ls-Dyna program. The constitutive Cowper-Symonds material model with linear hardening strain to predict material plasticity is used. The results of implementation of stresses and strains from a blanking operation flat disc of a sheet of metal for deep-drawing process are presented. After the blanking process simulation, an implicit springback analysis is performed. Then a numerical analysis of cup forming from this flat disc plate was carried out. The analysis results are compared with one another through reading of the sheet thickness in several characteristic points and the overall height of the product.