A digital image correlation analysis on a sheet AA6061-T6 bi-failure specimen to predict static failure

摘要

The failure prediction on the mechanism of fracture in fine grained sheets is an unsolved problem in the framework of non-linear plastic damage and fracture mechanics. Several engineering ductile materials exhibit inelastic behaviour with corresponding large deformations. This work hence focuses on a bi-failure specimen made of an Aluminium alloy AA6061-T6 under a tensile loading circumstance with a geometry adapted to determine the failure phenomenon at high and low stress triaxiality states. A 3D non-contact full-field optical technique, Digital Image Correlation, DIC, is employed to process the experimental data in which the force/displacement response in addition to the internal fields are thereby documented. One of the purposes of the specimen's geometry is to test the robustness of proposed DIC procedure. So, to further pursue the failure phenomenon, an uncoupled model, Gurson-Tvergaard-Needleman (GTN), is computationally implemented using an explicit finite element analysis.