Study of the local and global deformation process of an aluminium alloy using full-field measurements

The yielding process of some aluminium alloys is often characterized by an inhomogeneous diffusion of shear bands during deformation, which cause oscillations in both the force level and the strain history. This phenomenon can be observed during a tensile test, however, in order to describe the mechanical behaviour of components at the continuum level, the hardening behaviour is usually calibrated according to the averaged stress vs strain curve. In this paper an inverse method and full-field measurement were used to identify the hardening behaviour in different zones of the specimen. Different stress/strain curves were obtained at different zones of the test, showing that, at the mesoscopic level, the material can be described as a heterogenous material. The difference in the hardening curves is consistent with the occurrence of the strain bands during deformation.