12. A Simulator to Optimize the Experimental Set-Up for Elasto-Plastic Material Characterization

In the field of material characterization, the use of Digital Image Correlation (DIC) is coupled with an inverse methodology, such as the Virtual Fields Method (VFM), is getting an increasing interest in the recent years. That allows identifying material properties by performing tests on specimens with heterogeneous stress-strain fields. Respects to standard techniques, VFM consents to reduce the number of tests required to identify complex constitutive models. However, that methodology is sensitive to the adopted experimental set-up. The specimen geometry and the parameters used in the DIC settings can influence remarkably the identification results. Therefore, a preliminary study is necessary to determine the best experimental set-up to apply. To this purpose a simulating procedure, which reproduces numerically the whole measurement chain, was developed. The simulator includes most of the experimental uncertainties typically present in DIC measurements, moreover is able to look at different specimen geometries. The simulator was used here to optimize the geometry of specimens to be used to identify the elasto-plastic behavior of isotropic materials.