Studies of corrosion on AA 6061 and AZ 61 friction stir welded plates

Abstract

A remarkably new welding process, namely friction stir welding (FSW) has reached a tremendous research interest on the present decade due to bonding of similar or dissimilar materials at solidus state. This welding technique is environment friendly and versatile. In specific, FSW can be used to join the high strength aluminium alloys and other dissimilar alloys that are difficult to weld by conventional fusion welding. The process parameters have a major role in changing the characterisation of the joint. In this work, three parameters of the weld, namely rotational speed (rpm), axial load (kN), and weld speed (mm/min) are considered. Three pairs of AA 6061 and AZ 61 plates were welded with three different sets of these parameters. The welded zone was immersed in corrosive solution of NaOH for six months period. Corrosion behaviour was studied with the help of SEM and EDAX. Through this investigation, the importance of weld parameters control for the study of effects on the susceptibility for corrosion on the welded region can be sought.