Electrochemical Characteristics of Intermetallic Phases in Al-Cu-Li Alloys

This study provides a comprehensive overview of the electrochemical characteristics of intermetallic compounds (IMCs) commonly encountered in the 3rd generation Al-Cu-Li alloys. The electrochemical measurements were carried out on a AA2070-T8 alloy and surrogate alloys that have the compositions of select IMCs, typically found in AA2070-T8. The effects of environmental variables such as [Cl-] and pH on the corrosion potential, pitting potential, repassivation potential, corrosion rate, and galvanic current of these IMCs were thoroughly evaluated utilizing the electrochemical microcell method. An electrochemical database was documented that covers eight groups of common IMCs in various Al alloys. The findings improve the understanding of interactions between matrix and IMCs in Al alloys, with implications for corrosion mitigation and new materials design.