Abstract: On the basis of preparing the friction stir welding joint of 5383 Al alloy under different welding conditions, the macrocosmic appearance and the microcosmic appearance are all researched, and the effects of welding parameters, such as welding speed, stirring head speed and pressure, on the corrosion resistance of joint are obtained . The results show that the “S” line appears in the weld zone under certain welding conditions. The most serious region of corrosion is the “S” line, which results from three factors: the segregation of Mg, the aggregation of many micropores, and the formation of ferromanganese compounds. The corrosion resistance of weld zone other than “S” line and its nearby regions is better than that of the parent metal. Moreover, the reasons why the three factors make the corrosion resistance decrease are analyzed. The effects of different welding parameters on the “S” line are described. Decreasing the welding speed , increasing the stirring head speed and pressure can improve the corrosion resistance of friction stir welding joint of 5383 Al alloy.

Key words: 5383 Al alloy, Corrosion resistance, Friction stir welding, Welding parameters