Modeling of hole-expansion of AA6022-T4 aluminum sheets with anisotropic non-quadratic yield functions

10th International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Processes

Korkolis, Yannis P.^1 ; Brownell, Benjamin^1 ; Coppieters, Sam^2 ; Tian, Haobin^3

U. of New Hampshire, United States^1

KU Leuven, Technology Campus Ghent, Belgium^2

Shanghai Second Polytechnic U., China^3

关键词: D. digital image correlation (DIC);    Full strain fields;    Hardening curves;    Hole expansions;    Non-quadratic yield function;    Rolling direction;    Shell element;    Strain evolution;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/734/3/032083/pdf
DOI  :  10.1088/1742-6596/734/3/032083

来源: IOP

【 摘 要 】

In the hole-expansion of anisotropic AA6022-T4 sheets, the strain around the hole is non-uniformly distributed due to the anisotropy of the material. This was examined by performing experiments with a flat-headed punch and using Digital Image Correlation (DIC). In the experiments, failure always initiated at a unique location, oriented at 45° to the Rolling Direction of the sheet. The use of DIC allowed the probing of the full-strain-field in real-time. Subsequently, the experiments were simulated in DYNAFORM using shell elements and the Yld2000-2D anisotropic non-quadratic yield function, properly calibrated for this material. In addition, the hardening curve of the material was inversely identified at large strains from the tail of the tensile test. The strain evolution is compared between the experiments and the model.