Application of a dislocation model for FE-process simulation

Abstract In the last years physically based models have been implemented successfully into FEM-programs in co-operation between the Institute for Metal Forming (IBF) and the Institute of Physical Metallurgy and Metal Physics (IMM) in Aachen. Physical microstructural modules and plastomechanic simulation programs have already been linked successfully for planar and axial symmetric applications in the field of forging and flat rolling. On the basis of the existing modules the simulation package has been extended for the 3-dimensional-FE-simulation of metal forming processes with an integrated remeshing algorithm for the data transfer after high deformation. This paper presents the integration of a physical model into a 3-dimensional-FE-simulation with an analytical multi-parameter concept, which uses three types of dislocation densities as the characteristic state variables. The current flow stress is subsequently calculated from the dislocation densities and transferred into the FEM-simulation. With this model it is possible to describe not only work hardening but also dynamic and static recovery. A rolling process of an Al-alloy is carried out at the IBF and simulated thermo-mechanically using the FE-program L arstran /S hape . In addition to the determination of plastomechanical values of the rolling process, the dynamic and static microstructural evolution are simulated.

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