Abstract
The influence of structural changes occurring during the total thermomechanical processing cycle of an Al alloy have been investigated and their contribution to the final extrudate structure analysed. It is shown that homogenization is necessary, both to allow some flexibility in the extrusion process and to achieve a satisfactory structure. Preheating before extrusion is investigated and it is suggested that a two-step operation offers advantages. Evidence is presented to show that substructure may be retained during the solution soak and age cycle, and that the extrusion process variables have only a small effect on tensile properties. The investigation also demonstrates that acceptable properties may be obtained in 2014 alloy by a press quench and age cycle.