Design of a die depended upon the variation of product size and of material strength - research on box-shaped reinforced bumper made of high-strength steel sheet II

摘要

The forming processes of box-shaped cross-section products by die bending using a high-strength 1180 MPa steel sheet were studied. In a previous paper, the optimum shape of a die was determined. This paper describes the formabillty on the occasion of varying the product size and the strength of material. As for varying the product size, the forming processes using the newly developed dies were analyzed by FEM and it was found that the target shape could be obtained by simply changing the die dimensions of width and height. As for varying the strength of material, it was clarified that the influence of the U-bending processes direction on the final shape of the product was negligible and approximately identical shapes were obtained by changing the punch travels in the C-bending process. Furthermore, it was shown that the energy absorption of the novel product was superior to that of conventional one.