On the local corrosion behavior of coupled welded zones of the 2098-T351 Al-Cu-Li alloy produced by Friction Stir Welding (FSW): An amperometric and potentiometric microelectrochemical investigation

Localized electrochemical methods supported by surface analytical characterizations were employed to investigate galvanic coupling effects and local activity developed along the welded zones in Friction Stir Welded 2098-T351 Al-Cu-Li alloy. The investigation was carried out coupled weld joint/heat affected (WJ/HAZ) for both, retreating (RS) advancing (AS) sides. correlation between chemistry, microstructural characteristics of these areas studied. results showed development interactions within WJ HAZ regions, which imaged using scanning vibrating electrode technique (SVET), microscopy (SECM). SVET analyses that more susceptible anodic sites than WJ. SECM amperometric operation mode exhibited higher oxygen consumption cathodic compared HAZ. Furthermore, potentiometric alkalinization around increased acidity HAZ, mainly at severe localized corrosion (SLC). Based on combination with analyses, it is proposed microgalvanic cells formed are due presence secondary phases alloy their adjacent matrix.