Tribological and microstructural evaluation of friction stir processed Al2024 alloy

In this study, a new processing technique, friction stir processing (FSP) was applied to Al2024-T4 as a means to enhance the near-surface material properties. Samples were subjected to FSP using a constant tool rotating rate of 800 rpm and travel speed of 25 mm/min with a tool tilt angle of 3°. Microstructural evolution and tribological behavior of friction stir processed (FSP) Al2024-T4 were investigated. Microstructural characteristics of the samples were investigated by optical microscopy (OM) and scanning electron microscopy (SEM). Evaluations of mechanical properties include micro-hardness and wear resistance. Dry sliding wear tests were applied using a reciprocating wear test. The results showed that FSP was beneficial concerning improvement of hardness and wear resistance. FSP reduced friction coefficient by approximately 30% and wear rate by an order of magnitude.