Abstract: A hyperelastic-plastic constitutive relation is established based on intermediate configuration and the second lava of thermal dynamics. Updated Lagrangian equilibrium equations are derived through consistent transformation of the special weak equilibrium equations, after which the Newton-Rephson iterative solution formula of the nonlinear equilibrium equations are given by consistent linearization. An overall finite element simulation on conical die wire drawing process is performed. These justified the effectiveness of the finite deformation elasto-plastic finite element method in die designing, forming process optimization and analysis on defects of final products.

Key words: Constitutive, Elasto-plasticity, Finite deformation, Finite element method