Metals

Abstract

The objective of this section is to present several studies that have dealt with the use of the VFM to identify elasto-plastic constitutive laws on metallic materials. In the first part, several studies focusing on monotonic quasi-static loadings using different sheet metal specimen geometries are summarized. These studies correspond to the early stages of the adaptation of the VFM to elasto-plasticity and present a gradual progression from simple to more complex situations. The most advanced version is then presented at the end of this first part with the use of cyclic loadings to identify a combined isotropic and kinematic hardening model. Significant progress in the virtual fields selection has also been made in this study. In the second part, a first example of the identification of a visco-plasticity model is presented using moderate strain rate tests where full advantage is taken of the presence of heterogeneous strain rate maps to identify strain rate sensitivity over a strain rate range of a decade with a single test. Finally, a first attempt at the identification of a spatially heterogeneous elasto-plastic law is presented with application of a steel girth weld and a titanium hybrid laser weld.