Numerical analysis on the effects of the friction coefficient on the deep drawing of a rail

This work focuses on the analysis of the friction coefficient effects on the deep drawing of a U-rail. This shape was selected for this study due to the simple deformation mechanisms that are involved, mainly bending and stretching, but also because it is a rail specially conceived to emphasize 2-D springback defects. This simplifies the evaluation of the influence of the friction coefficient during the forming and springback phases. The blank sheet material selected is high strength steel. The finite element simulations were carried out with the static implicit code DD3IMP. The plastic behaviour is modelled using the 1948 Hill's criterion with an isotropic and kinematic hardening. Simulations were performed over a wide range of a global constant friction coefficient for all tools, between 0.050 and 0.250. For two constant values of the global friction coefficient (0.100 and 0.150) the friction coefficient of the die radius was changed, over the same range of values between 0.050 and 0.250.