Lehrstuhl für Fertigungstechnologie, Universität Erlangen-Nürnberg

Investigations on the determined control of the material flow in sheet metal hydroforming



Datum: 30.11.2004


Author


Reporter

  • Prof. Dr.-Ing. Dr.-Ing. E.h. mult. Dr.h.c. M. Geiger
  • Prof. Dr.-Ing. K. Roll, UniversitÌt Stuttgart

Lightweight design is a strongly ongoing trend especially in the automotive industry, following the cultural and legal expectations towards environmental friendly products. The development activities in the car body production concentrate on modern lightweight materials, new car body concepts and innovative design solutions as well as on new manufacturing technologies. One of these technologies, the hydroforming of sheet metal pairs, is still at the beginning of its industrial realisation, especially because of the lacking knowledge of promising process strategies for the forming of complex structures. The main aim of this thesis was the systematic analysis of an active counter punch system used to influence the forming process in sheet metal hydroforming of a simplified model geometry. The performed investigations on the effect of tribology conditions, non-linear strain paths and the used material model on the forming results in the FE-analysis enabled a deeper understanding of counter punch assisted processes. Significantly improved results were achieved in a multi step forming process, which was mainly influenced by the punch movement, pressure control and friction conditions. The efficacy of the developed forming strategy as well as the evaluation of the influencing factors was finally validated and verified by laboratory trials.