Experimental and Numerical Modelling of Thermo-Forming of Anisotropic Thin Sheet

Abstract : Coupled constitutive equations, formulated in the framework of the thermodynamics of irreversible processes accounting for isotropic hardening as well as the isotropic ductile damage are used to simulate numerically, by the Finite Element Analysis, 3D metal hydroforming processes. The experimental study is dedicated to the identification of stress-strain flow and damage parameters by using the Nelder-Mead simplex algorithm optimization from the global measure of displacement and force. Applications are made to the simulation of thin sheet thermohydroforming using different die geometry to show the efficiency of the proposed methodology and to localize plastic instability, thinning of sheet and damage initiation under different forming conditions.