Development of an Earing Model with Consideration for the Crystallographic Texture of Sheet Metal During Axisymmetric Drawing

A calculation model is developed for earing during cylindrical drawing of metallic materials, which is based on the phenomenological criterion of plasticity taking into account the crystallographic texture of the material. The model was verified by comparing the calculated earing defects with those observed in drawing tests on an aluminum preform. Further modeling shows that deformation orientations ({112}<111>, {110}<112>, {123}<634>, and {100}<011>) lead to earing at an angle of 45° to the rolling direction, while recrystallization orientations ({100}<001> and {110}<001>) lead to earing in the rolling and transverse directions. Crystallographic orientation {110}<001> gives maximum earing, while orientation {123}<634> causes minimum one. In all the cases, the contribution of plastic anisotropy and yield stress anisotropy to earing is almost the same, with a slight predominance of the latter. The earing behavior is shown by the example of materials with a two-component ({112}<111> + {100}<001) texture: as the fraction of the {112}<111> orientation grows, ears in the rolling and transverse directions are reduced, while they form at an angle of 45° to the rolling direction. Considering such influence, the earing coefficient is minimum at 55–60% of the {112}<111> component.