The Influence of Homogenization Treatment on Aging Response of 6063 Aluminium Alloy

Abstract

This paper reports the effect of homogenization treatment on T6 tempering of 6063 aluminium alloy. Wrought 6063 aluminium sample was machined into tensile and impact tests specimens. Samples were also cut for hardness and metallographic works. These samples were divided into two groups; group I samples were homogenised at 570ºC for 2, 2.5, 3 and 3.5 hours respectively prior to T6 temper while group II samples were T6 tempered without prior homogenization. The heat treated samples was subjected to tensile, impact and hardness tests and the evolved microstructures was characterised using a scanning electron microscope equipped with energy dispersive spectrometer. The results show improvement in the mechanical properties for those samples homogenized prior to aging as compared to conventionally aged samples and there was also an unusual combination of mechanical properties in terms of ductility, toughness and strength. The resulting microstructures shows the presence of rod-like phases in the as-received and T6 tempered samples while group II samples contain spherical precipitates. The overall result showed that prior homogenization can prevent the usual concomitant decrease in ductility and toughness of T6 tempered 6063 aluminium alloy.