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Many metallic sheets exhibit a certain initially plastic anisotropy that influences considerably the mechanical behaviour of the sheet material in forming operations. Nowadays, computer modelling based on the finite element method (FEM) in conjunction with the concept of anisotropic yield functions is successfully utilized to design sheet forming processes. The yield function applied in the FEM analysis affects very strongly the computed results such as material flow, springback, wrinkling and limiting strains. Consequently, in order to increase the accuracy of the FEM simulations the yield function used should be as accurate as possible in order to capture all the important anisotropy effects.In this paper, the new plane stress yield function for orthotropic sheet metals recently introduced by the author (Aretz H 2003 J. Mater. Process. Technol. submitted) is applied to orthotropic steel and aluminium sheet metals. The yield function contains eight anisotropy parameters that may be fitted by means of a Newton solver or a least square solver to selected experimental input data. The main attractiveness of the new yield function lies in its very simple mathematical form, which makes it very effective and thus quite interesting for implementation in finite element codes. The capabilities of the new yield function are demonstrated by applications to selected orthotropic sheet materials.

The complete through-process modelling of crystallographic texture evolution during aluminium sheet production is addressed. The texture determining processes deformation and recrystallization are analysed with respect to the underlying mechanisms. The advanced deformation texture model grain interaction (GIA) is coupled to a statistical analytical recrystallization texture model (StaRT). New concepts are described to model nucleation spectra for recrystallization with the GIA model and with a new model for the prediction of in grain orientation gradients. Orientation dependent recovery of the deformed structure is reflected based on substructure information extracted from the GIA model. A finite element (FE) model incorporating dislocation density based work hardening as well as texture serves as a process model to describe the macroscopic production parameters based on microstructural information. More detailed information on this integrative FE model can be found in a second paper presented at this symposium by Neumann et al. The excellent performance of the outlined through-process texture modelling concept is demonstrated in applications for two different aluminium sheet production lines—one laboratory and one industrial process—and displays for the first time the possibility of modelling texture evolution throughout various consecutive processing steps.