A new strategy for the simultaneous identification of constitutive laws parameters of metal sheets using a single test

An inverse analysis methodology for determining the parameters of plastic constitutive models is proposed. This involves the identification of the yield criterion and work-hardening law parameters, which best describe the results of the biaxial tensile test on cruciform samples of metal sheets. The influence and sensitivity of the constitutive parameters on the biaxial tensile test results is studied following a forward analysis, based on finite element simulations. Afterwards, the inverse analysis methodology is established, by evaluating the relative difference between numerical and experimental results of the biaxial tensile test, namely the load evolution in function of the displacements of the grips and the equivalent strain distribution, at a given moment of the test, along the axes of the sample. This methodology is compared with a classical identification strategy and proves to be an efficient alternative, allowing to avoid time-consuming tests, some of them hard to analyse and liable to uncertainties.