Investigation of Upsetting with Curved Dies Through Analytical and Numerical Methods

摘要

The main objective of this study is to investigate the stress distributions within the deformation zone in upsetting of a strain-hardening material by curved dies of arbitrary shape through analytical slab method and finite element simulation. The geometrical profile of the die surface is constituted by a two-degree polynomial function with three arbitrary coefficients. The variation of normal pressure along the die surface of contact and various coefficients values related to geometrical profile of die surfaces on stress state distributions are examined. In addition, the effect of interface frictions on normal pressure distributions along the die surface of contact for perfectly plastic material is also investigated. The results obtained from analytical solution with slab method are confirmed with those obtain from finite element analysis with DEFORM 2D which is utilized in this study to simulate the deformation characteristics of upsetting with convex curve dies. Finally, the forming load was calculated and compared to those obtained by DEFORM 2D and Vilotic et al., and there is a good consistency among them.