The facet method for plastic anisotropy of textured materials

Abstract

The Facet method is a new approach to implement the plastic anisotropic behaviour of polycrystalline materials in finite-element models for simulating metal forming processes. It employs analytical expressions of plastic potentials in strain rate space and/or stress space. The parameters in these expressions are obtained by fitting to the predictions of a multilevel model for the plastic deformation of a textured material. The resulting equipotential surfaces in strain rate space and yield loci in stress space are automatically convex. Examples of q-values and uniaxial yield stress variations as obtained with the Facet method in combination with the Taylor theory are shown for three industrial sheet metals. The results are compared to the ones calculated directly from the Taylor theory and those obtained with the Quantic method.