The effect of pin shape on the corrosion behaviour of friction stir welded 1080 aluminium alloy

ABSTRACT

This paper aims to investigate the effects of different pin shapes on the corrosion behaviour of the friction stir welded (FSW_ed) joints. Friction stir welding (FSW) of 1080 aluminium alloy was done with the Taguchi L₉ orthogonal design using three-pin shapes including cylindrical, square, and triangle. The corrosion behaviour of welded samples was studied using the weight loss and potentiodynamic polarisation methods. Results revealed that the corrosion resistance of samples welded by cylindrical pin shape is higher than that of the samples welded by square and triangle pin shapes. Optical microscopy and scanning electron microscopy (SEM) were employed to investigate the corroded surface. The observations showed that the samples welded by cylindrical pin have better surface quality and less corrosion features than the samples welded by square and triangle pins in 3.5 wt.% NaCl solution. Furthermore, the microstructure analysis approved that decrease in grain size leads to higher corrosion.

KEYWORDS:

• Friction stir welding (FSW)
• corrosion behaviour
• pin shape
• potentiodynamic polarisation
• grain size

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests.