Evaluation of crush performance of extruded aluminum alloy tubes based on finite element analysis with ductile fracture modeling

In this study, the crush performance of four aluminum extrusions are investigated through analysis based on finite element (FE) simulation incorporating experiment-numerical hybrid ductile fracture modeling. Tensile tests on standard and non-standard specimens, coupled with digital image correlation and FE analyses, are employed to establish constitutive models for the materials. The evaluation of crush performance is performed based on both axial crush test and corresponding 3-dimensional FE simulation, which could validate the employed plasticity and fracture laws and predict crush performance indicators with reliable accuracy. Additionally, FE modeling enables thorough analysis of highly non-proportional loading paths and potential crack initiation sites, with the crack formation mechanism elucidated through the evolution of a proposed damage variable. Furthermore, the modified crush performance indicators are newly suggested, which could explain the dependence on both the absorbed energy of tubular extrusion and properties of ductile fracture.