Corrosion Behavior of the Friction Stir Weld of 2024 Aluminum Alloy in Salt Solution

The full immersion etching method was utilized to study the corrosion properties of the base material and friction stir weld (FSW) of 2024 aluminum alloy in salt solution environment. The corrosion rate was calaulated and the corrosion morphology was observed. The results show that the corrosion started from pitting and finally became exfoliation corrosion. The corrosion rate on different narrow areas of weld joint followed the rule:heat affected area and welding area > thermo-mechanically affected zone > base area. The corrosion rate of the FSW weld was faster than that of base material and the corrosion resistance of FSW weld was worse than that of base material.