Simulation of Crystallographic Texture After High Temperature Axisymmetric Extrusion of Aluminum Alloys

The application of aluminum extrusion alloys in the automotive sector requires careful control of microstructure during thermomechanical processing, in particular, the crystallographic texture and associated anisotropy which significantly impacts mechanical behavior of the extrudates. The present study examines the microstructure evolution in an Al–Mn–Fe–Si alloy after high temperature extrusion. An in-house phase-field code for high performance computing platforms is employed to study the microstructure changes during annealing. Synthetic 2D microstructures were generated where the initial subgrain size and disorientation distributions were informed from EBSD measurements of the deformed state obtained in a high temperature asymmetric extrusion experiment. The simulations showed that the presence of a small fraction of subgrains with non-ideal crystallographic orientations significantly affected the final crystallographic texture consistent with experimental observations. It was also shown that the spatial position of these non-ideal orientations can also impact the evolution of texture and final microstructure. As such, the proposed modeling approach has potential to be a valuable tool for through process models of high temperature extrusion, particularly for predicting the final crystallographic texture.