Simulation of the fracture behavior of Al6061 laser welded joints with the Rousselier model

Abstract Ductile fracture behavior of an aluminum laser beam welded joint is investigated experimentally and numerically. Based on the hardness test across the welded joints, the dimensions of different weld regions are fixed. Tensile tests of flat specimens extracted from the base material, from the fusion zone and from the heat affected zone are made. The mechanical properties of the different weld regions are used as finite element model input in the simulation work. Fracture toughness tests are performed on compact tension specimens with the initial crack located in the base material, and in the center of the fusion zone, respectively. The tensile test results of compact tension specimens are shown in the form of force vs. crack opening displacement and fracture resistance curves. Based on the numerical calibration of the Rousselier parameters on notched round specimens, the Rousselier model is used to investigate the crack propagation of the compact tension specimen. Good agreement between the numerical and experimental results is obtained from compact tension specimens with the initial crack located at different positions of the weld region.