The analysis of flange deformation is important in that major deformation occurs in the flange portion of drawn cups. The effect of anisotropy plays a great role in determining the ear development.
In the present study the rigid-plastic finite element method incorporating a general formulation for anisotropic sheet metal is used for the analysis of flange deformation. In order take into account the effect of geometric change during an incremental step a convective coordinate system is used and an explicit relationship for effective strain increment is introduced on the basis of appropriate assumptions in deformation path and rotation of anisotropic axis during a deformation step.
The complicated non-axisymmetric deep-drawing process is simplified by flange deformation in which a fixed displacement is given in the in-plane normal direction to each nodal point. At an interval of several steps inner mesh layer flowing into the die cavity is eliminated so that the inner boundary is eliminated and then remeshed.
Experiments are carried out for punch shapes of circle, ellipse, clover and rounded square. Comparison between computation and experiment shows that these is a good agreement in flange deformation.
