Multiscale modelling of plastic deformation of polycrystals: implementation of texture-based anisotropy in engineering applications (FE codes for forming, prediction of forming limit curves

摘要

Finite element models for metal forming are used to design and optimise industrial forming processes. The limit strain in sheet metal forming can be predicted for monotonic loading or strain paths with changes. Models like these should be as accurate as possible in order to be useful, and hence take the texture, microstructure and substructure (dislocation patterns) into account. To achieve this, a hierarchical type of modelling is proposed in order to maintain the balance between calculation speed (required for engineering applications) and accuracy. In that case, FE models to be used at the engineering length scale work with an analytical constitutive model, the parameters of which are identified using results of multilevel models (meso-scale with an homogenisation procedure). The analytical model to be used at macro-scale will be discussed, as well as the identifications procedure. The later make use of meso-scale models. Finally an example will be given (formability of a sheet material).