The effect of iron (Fe) level on the bendability of three Fe-variants of AA6111 sheet (i.e. 0.06, 0.26 and 0.68 wt.% Fe) is investigated using an instrumented cantilever bend test (CBT) apparatus. The tests are also simulated in a finite element method (FEM) model which employs a isotropic–kinematic hardening version of the Gurson–Tvergaard–Needleman (GTN) constitutive softening equations. Experimentally, increasing Fe content level is found to decrease bendability. This trend is attributed to an increasing volume fraction of void-nucleating particles, particularly within first-order clusters, and is demonstrated by a series of GTN-based FEM model predictions.
Keywords:
AA6111 sheet; Bendability; Fe content; Gurson; Damage