Behavior of sheet metal submitted to cyclic bending and stationary drawing deformation

A sheet metal deformation process based upon bending combined with drawing has been developed with FEM numerical simulation assisted with simple experimental device. Careful experimental measurements combined with 3D numerical simulation identified the more relevant parameters and pointed out to several applications, among them controlled work hardening and plastic anisotropy measurement. Combining a nearly cyclic bending deformation path with a steady-state drawing promotes very high levels of effective strain and stress, even without apparent macrostrains. The numerical simulation of bend/drawing forecasts that deformation ratio ε2/ε3 on the strip is related to the Lankford anisotropy plastic coefficient measured by the uniaxial tensile test. Experimental measurements confirm this trend, pointing out to a new method to estimate Lankford coefficients.