Effect of friction stir processing on electrical conductivity and corrosion resistance of AA6063-T6 Al alloy

Abstract

The aim of this paper is to study the effect of friction stir processing (FSP) on electrical conductivity and corrosion resistance of AA6063-T6 Al alloy. Also, the microstructural and mechanical characteristics were examined. Different samples were structured by employing a constant feed rate (ν) of 120 mm/min and different rotating speeds (ω) of 250, 315, 400, 500, 630, and 800 r/min. The results showed that FSP significantly refines the microstructure of the AA6063-T6 Al alloy. Increasing the rotational speed increases the grain size in the centres of stirred zones (SZ). The FSP significantly increases the electrical conductivity of the alloy. The highest electrical conductivities were observed at the centres of the SZ for the alloys processed with varying rotational speeds between 315 and 500 r/min. Increasing the rotational speed above this range tends to reduce the electrical conductivity, but it is still higher than the base material. In contrast, the corrosion resistance was found to decrease due to FSP of the AA6063-T6 aluminium alloy. It has been found that, increasing the rotational speed decreases the corrosion resistance of the SZ in 1 M HCl solution.