Corrosion Resistance Properties of Welded Joints of Aluminum Alloys Containing Trace Sc

Al-Mg alloy containing trace Sc was prepared via melting-casting.The joints of the Al-Mg alloy were welded by using manual argon-arc welding technology.Neutral salt spray and exfoliation corrosion properties of the welded joints were investigated and the microstructures of the welded joints were observed under optical microscope and transmission electron microscope.Corrosion mechanism of the alloy was also involved.The results showed that with trace Sc,the grains of alloys was refined effectively,and the corrosion resistance of the welded joints was improved remarkably.It is belived that free of continuous precipitation or network in grain boundary contributes to good corrosion resistance.