Investigating Into the Corrosion Behavior of Friction Stir Welding of 2024 Aluminum Alloy by Standard Scanning Kelvin Probe Method

In the present study, the corrosion behavior of projection friction stir spot welding of 2024 aluminum alloy has been investigated and compared with the corrosion behavior of the base metal. Welding of sample was performed with the rotation speed of 2500 rpm and the dwell time of 12 seconds. The penetration depth of the tool on the surface of the sample was 0.1 mm, the diameter of the tool was 16 mm, and a circular protrusion with a diameter of 10 mm and a height of 0.4 mm was placed below the working table. By using Tafel polarization test method and standard Scanning Kelvin Probe through potential chang of weld surfaces and base metal as well as chang in corrosion current density, the corrosion behavior of projection friction stir spot welding was investigated. The results showed that the corrosion potential of the weld area is reduced compared to the base metal, although this reduction has not led to a significant increase in corrosion current density. Also, the welding zone has higher corrosion current density than the base metal region.