Prediction and control of subgrain size in the hot extrusion of aluminium alloys with feeder plates

It is widely recognised that subgrain size has significant influence on the strength and ductility of metals. Modelling of subgrain size evolution is essential for the detailed understanding and control of mechanical properties. In the present paper, the evolutions of subgrain size during hot extrusion of various aluminium alloys are first predicted. The microstructural models are then applied to the extrusion of a thin wide semi-closed section using a feeder plate. The feeder plate is investigated by comparing forward extrusion with and without the plate. Results such as temperature, velocity profile, microstructure and pressure distribution are discussed. The influence of the die configuration and the suitability of using several tuning parameters for each alloy are also discussed.