Abstract
Abstract
In this study, the surface microhardness, friction and wear performance of recycled aluminium alloy 6063 were improved via an energy-efficient surface engineering technique known as friction stir processing. Different tool rotational speeds of 1200 rpm, 1400 rpm, 1600 rpm, 1800 rpm and 2000 rpm with a fixed feed rate of 30 mm/min were used to process the recycled aluminium alloy 6063. The effects of rotational speed on the microstructure, surface microhardness and tribological performance of the samples were analyzed. The results show that the samples produced at a stirring speed of 1200 rpm achieved the greatest enhancement of 25 % in surface microhardness, 37 % in wear resistance and 33 % reduction in friction coefficient. This has significant implications for environmental sustainability as a relatively low rotational speed, hence a low energy input, is sufficient to enhance the surface properties of recycled aluminium alloy 6063. The benefits of superior tribological properties of recycled aluminium alloy afforded by such an energy-efficient surface engineering method include reduced exploitation of new resources, reduced carbon footprint, and enhanced product sustainability and durability.