Article I. Statistical models for deformation texture prediction using vortex-type accommodation of local strain misfits

Abstract

Many advanced models for deformation texture prediction make use of crystal plasticity finite element or fast Fourier methods. They manage to deal with strain heterogeneities at very small length scales. However, they demand a lot of calculation power, too much for daily use as tools for computer aided design/manufacturing of forming operations of steel or aluminium sheet parts. So-called statistical models for deformation texture and plastic anisotropy are still of interest in such cases, as they are fast and can indeed be incorporated as constitutive models in finite element simulations of metal forming processes. The present work discusses the existing statistical models. Predicted ODFs of rolling textures of a few steel and aluminium alloys will be compared with those of older models as well as with experimental results. A currently undertaken attempt to further improve the quality of the predictions of one of the statistical models (ALAMEL) will be proposed. Not only the effect of local deviations from homogeneous strain ('relaxations') on the plastic work in the grains will be considered, but also the increase of plastic work due to the plastic accommodation of these misfits. This is done by assuming the existence of certain flow patterns in the matrix surrounding the grains, some of which resembling the 'vortices' sometimes observed in liqsuids.