Analysis of the Bridgman procedure to characterize the mechanical behavior of materials in the tensile test: Experiments and simulation

This note presents an experimental analysis and a numerical simulation of the mechanical behavior experienced by cylindrical specimens of pure copper during the tensile test. A set of experiments has been carried out in order to derive the hardening parameters that characterize the material response. The simulation of the deformation process during the whole test is performed with a finite element large strain elastoplasticity-based formulation. The results of the simulation show that the mechanical characterization involving the classical Bridgman correction factor, defined in terms of logarithmic strains and aimed at predicting the stress distribution at the necking zone, cannot properly describe the hardening response for this material. Therefore, the use of a different correction factor, which consequently leads to another set of hardening parameters, is proposed. Finally, an adequate experimental validation of the numerical results is obtained for this last case.