Thermo-mechanical simulation of microstructure and texture evolution in flat-strip extrusion of Al–Mg–Si-Cu alloy

Abstract

Enhancing the mechanical properties of aluminium extrusions has been a subject of industrial interest for many years. Conventional approaches focused on tuning the extrusion parameters and have established correlations with the final microstructure, but a mechanistic understanding of how microstructures evolve during extrusion remains limited. To address this, a physical simulation methodology was developed for flat-strip extrusion, allowing detailed examination of microstructural evolution and providing a pathway for future microstructure and texture design. Currently, this work focuses on physically reproducing the microstructure and texture of the central region of an industrially extruded Al-Mg-Si-Cu flat strip by replicating its strain path. The microstructures and textures simulated using a Gleeble thermomechanical simulator were compared with industrial extrusion to assess the fidelity of the approach. The results demonstrate that the simulation at 580 °C reproduced elongated grain shape, dominant < 112>//ED texture and morphology of the intermetallics which are the key features of strip extrusion. Quantitative comparisons revealed close agreement in microstructure and texture, with limited differences. Overall, the study confirms that this method provides a reliable framework for capturing the deformation conditions of flat-strip extrusion. Beyond validation, the present approach provides a versatile platform for future studies aimed at investigating the onset and progression of recrystallisation, second-phase particle evolution, and strain path effects through systematic characterisation of microstructure at intermediate strain levels.