Finite element simulations of sheet-metal forming processes for planar-anisotropic materials

Sheet-metal forming simulations are made using a plane-stress yield function proposed by Ferron et al. for orthotropic sheets. Following the general method for the integration of rate-independent plasticity models, the yield function has been implemented in the implicit Abaqus/Standard finite element code. Simple forming operations are simulated, such as the hemispherical punch test and the cup drawing test. The combined effects of rheological and tribological parameters on the strain distributions and the limits to formability are analysed, and discussed in relation with improved descriptions of the yield surface. Also, the magnitude of ears predicted for the cup drawing test is compared with experimental values on tin-plate steel.