The corrosion inhibition mechanisms of Ce(III) ions and triethanolamine on graphite—AA2024-T3 galvanic couples revealed by localised electrochemical techniques. (15th April 2019)

• Record Type: Journal Article
• Authors: Coelho, L.B.; Taryba, M.; Alves, M.; Noirfalise, X.; Montemor, M.F.; Olivier, M.-G.
• Is Part Of: Corrosion science. Volume 150(2019)
• Page Start: 207
• Page End: 217
• Publication Date: 2019-04-15
• Subjects: A. AA2024 -- A. Galvanic couple -- A. Cerium -- B. SEM -- C. Corrosion -- C. Corrosion inhibitor; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.02.007
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: Inhibitive effects of CeCl3 /triethanolamine on AA2024/graphite couples were revealed. SVET/SIET tests showed that inhibition mechanisms depend on the electrodes area ratio. CeCl3 inhibited localised corrosion of AA2024-T3 (trenching, IGC) coupled to graphite. Triethanolamine formed complexes with Cu ions when Cu-rich particles were active. Abstract: The inhibition mechanism of cerium chloride and triethanolamine on the galvanic corrosion of AA2024-T3/graphite in NaCl electrolyte was investigated by localised electrochemical techniques. Quasi-simultaneous measurements of ionic current densities and pH were performed by the Scanning Vibrating Electrode Technique (SVET) and Scanning Ion-Selective Electrode Technique (SIET). Surfaces were analysed by Scanning Electron Microscopy coupled with Energy Dispersive X-ray (SEM-EDX) and X-Ray Photoelectron Spectroscopy (XPS). This work follows a recent publication (Coelho et al. 2018) and discusses the effect of inhibitors on two AA2024-T3/graphite galvanic couples, constructed with two different areas ratio, evidencing that this parameter significantly influences the corrosion and corrosion inhibition process.