TEMPERATURE DEPENDENT FRICTION MODELING FOR SHEET METAL FORMING

Stainless steel in sheet metal forming processes show a hardening behavior, which can be described only in dependency of the deformation and temperature history. Because of the temperature influence to the material properties, the temperature dependence of the friction in the process has to be taken into account. Friction tests using different temperatures showed a change of the friction regime. From the experimental observation the temperature and velocity dependence of the friction was modeled and integrated in a finite element code for metal forming. On the macroscopic scale the temperature and velocity dependent friction was integrated in a FEM code of metal forming. The FEM simulation has been applied to the biaxial stretching test and compared with the experiment. The numerical results showed a good agreement with the failure behavior of the stainless steel.