Lehrstuhl für Fertigungstechnologie, Universität Erlangen-Nürnberg

Material behaviour in micro blanking and bending processes



Datum: 26.05.2003


Author


Reporter

  • Prof. Dr.-Ing. Dr.-Ing. E.H. mult. Dr.h.c. M. Geiger
  • Prof. Dr.-Ing. P. Groche, TU Darmstadt

The trend toward miniaturisation of technical products leads to an increased demand for metallic parts with dimensions smaller and smaller. Sheet metal working processes make it possible to produce such parts economically, but the close tolerances make high demands on the process design. Additionally, effects caused by the miniaturisation itself come along: for instance, in the case of a forming process with dimensions in the range of 100 micrometer only a few grains are located in the deformed area. Therefore, it is not permissible to assume homogeneous material as in the case of forming processes with conventional dimensions. As a result, specific characteristics occur, which are investigated within the presented thesis. The effects of tool geometry and parameters of the material are investigated carrying out punching and blanking processes of thin sheets. The process forces, the material flow and the geometry of the workpiece after the process are analysed applying a purpose-built tool with measuring technique adjusted to the small dimensions and an optical measurement system, respectively. The influence of the anisotropy of the material on punching processes and the effect of inhomogeneous material during a bending process are described. The obtained knowledge enables an improved process design and a higher accuracy of the workpieces.