An anisotropic stress based criterion to predict the formability and the fracture mechanism of textured zinc sheets

The Forming Limit Diagram (FLD) of a textured zinc sheet has been identified via tensile and bulge tests. The strong anisotropy of the sheet is reflected in the tensile tests, and even more strikingly in the formability measured from the bulge tests. The dependence of the FLD on the orientation of the sheet is unusual, and is shown to be well captured by an anisotropic stress based criterion. The criterion is also able to predict the observed cracks orientations.