Finite-Element-Simulation of Metal Forming Processes Using Two Different Material-Laws

  • A. Erman Tekkaya
  • Karl Roll
  • Jürgen Gerhardt
  • Martin Herrmann
  • Guohi Du
Conference paper
Part of the Berichte aus dem Institut für Umformtechnik der Universität Stuttgart book series (IFU, volume 85)

Summary

Different kinds of finite-element approaches are available to simulate metal-forming processes. For bulk metal forming, the basic differences between these approaches arise from the constitutive equations modeling the material behaviour. The appropriate choice of the material law depends onto the aims of the analysis (such as the kind of results sought for) and the physical nature of the problem.

In this paper, firstly, the theoretical backgrounds for the implementation of two finite-elementmethods based on rigid- and elastic-plastic constitutive laws are described. Although both of the methods build up on the v. Mises yield criterion, the former is based on the Levy-Mises flow rule, whereas the latter one on a generalized Prandtl-Reuss flow rule. Furthermore, for the elastic-plastic material law, the non-linear kinematics are of prime importance. Secondly, the paper presents comparative numerical studies with the two approaches for selected metal-forming problems such as upsetting, rod-extrusion and cup-extrusion. Finally, some examples of industrial applications of finite-element simulations are given as the determination of residual stresses in workpieces formed through containerless extrusion, rod-extrusion, tube-extrusion. upsetting and drawing, and the analysis of combined forming processes. Special emphasis is given to to industrial utilization of the simulation methods.

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Copyright information

© Springer-Verlag, Berlin, Heidelberg 1986

Authors and Affiliations

  • A. Erman Tekkaya
    • 1
  • Karl Roll
    • 2
  • Jürgen Gerhardt
    • 1
  • Martin Herrmann
    • 1
  • Guohi Du
    • 1
  1. 1.Institut für UmformtechnikUniversität StuttgartStuttgartGermany
  2. 2.Control Data GmbHStuttgartGermany

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