The presentation deals with the effect of non-proportional loading paths on damage and failure behavior of ductile sheet-metals.
The proposed continuum damage model is based on a damage criterion and a damage law both depending on stress triaxiality and the Lode parameter. Consequently, the continuum model can reflect different stress-state-dependent damage and failure mechanisms acting on the micro-level like growth of voids for more elevated stress triaxialities and formation of micro-shear-cracks for lower or negative stress triaxialities.
Recently, new specimens have been proposed for in-plane biaxial testing. These specimens can be applied under a big variety of loading conditions generating different stress states leading to different damage and fracture mechanisms. In addition, these specimens are also applicable to study the material behavior under non-proportional loading paths. In this context, new results are presented for the aluminum-alloy EN AW-6082 including strain fields reported by digital image correlation, fracture surfaces studied by scanning electron microscopy and images of the fractured specimens. These experimental data can be used to validate damage and fracture models for the investigated aluminum-alloy and, thus, to facilitate numerical simulations.