The effect of modeling parameters and bending on two-dimensional sheet metal forming simulation

This paper gives a short summary of a new approximate method to include bending stiffness into an implicit membrane FEM formulation for axisymmetric multi-stage drawing problems. It compares analyses of round cup drawing processes using pure membrane elements with those employing the new formulation. The sensitivity of the maximum required forming force, the draw-in of the sheet rim, and the true strain distributions to small changes in a variety of modeling, material, and process parameters is investigated for both the membrane and bending formulations. Those parameters that influence the accuracy of the numerical solution most significantly are identified, and recommendations for the optimum choice of parameters are made.