Performance assessment of inverse methods in large strain plasticity

The Virtual Fields Method (VFM) is an inverse method which allows to identify the constitutive parameters of materials from full-field measurements. The method relies on the principle of virtual work and, traditionally, is mainly used to characterize the material properties. Nonetheless the VFM can also be used as an inspection tool to compare constitutive models or experimental configurations. For instance, it can be adopted to compare different constitutive models in order to find out which one is more suitable to describe the mechanical behaviour observed during an experiment. In this paper this idea is applied in the case of large strain plasticity. A sensitivity study was conducted to evaluate how the specimen geometry and the texture orientation influence the identification of the constitutive parameters. Then the method was used to compare the performances of three constitutive models in reproducing the plastic behaviour of a given material. The studied models are isotropic von Mises, Hill48 for normal and planar anisotropy. The work was conducted on simulated data. © The Society for Experimental Mechanics Inc. 2014.