Surface finishing effects on the corrosion behavior and electrochemical activity of 2098-T351 aluminum alloy investigated using scanning microelectrochemical techniques

Author(s)

da Silva, Rejane Maria P. ; Milagre, Mariana X. ; Izquierdo, Javier ; Betancor-Abreu, Abenchara Maria ; de Oliveira, Leandro A. ; Araujo, Joao Victor de S. ; Antunes, Renato A. ; Souto, Ricardo M. ; Costa, Isolda

• Document type: Journal article
• Source: MATERIALS CHARACTERIZATION; v. 191, p. 12-pg., 2022-07-18.

Abstract

The effects of surface finishing on the corrosion behavior and electrochemical activity of AA2098-T351 (Al-Cu-Li alloy) were investigated on the basis of the correlation between surface chemistry, microstructure and electrochemical activity. The alloy was evaluated in the as-received and polished conditions. The morphology of the two types of surfaces was investigated using confocal laser scanning microscopy (CLSM), optical microscopy and optical 3D profilometry. The surface chemistry was analyzed by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX). Scanning microelectrochemical techniques (namely, localized electrochemical impedance spectroscopy (LEIS), the scanning vibrating electrode technique (SVET) and scanning electrochemical microscopy (SECM) in potentiometric mode) were used to examine the electrochemical activity of the surfaces. The results showed that on the as-received surface, the near surface deformed layer (NSDL), which is composed of Mg-rich bands, influenced the corrosion activity of the alloy. Higher electrochemical activity and greater susceptibility to severe localized corrosion were related to the polished surface condition compared to the as-received one. (AU)

• FAPESP's process: 13/13235-6 - Investigation on the localized corrosion and the fatigue corrosion resistance of high strength aluminum alloys joined by friction stir welding (FSW)
• Grantee: Isolda Costa
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/11427-1 - Micro-electrochemical techniques to study the localized corrosion in Al-Cu-Li alloys joined by friction stir welding (FSW)
• Grantee: Rejane Maria Pereira da Silva
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 18/06880-6 - Use of Localized Electrochemical Techniques for the Study of Corrosion of of High Strength Aluminum Alloys Joined by Friction (FSW).
• Grantee: Rejane Maria Pereira da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral