Editors' Choice—Dealloying-Driven Cerium Precipitation on Intermetallic Particles in Aerospace Aluminium Alloys. Issue 4 (16th April 2021)

• Record Type: Journal Article
• Authors: Kosari, A.; Ahmadi, M.; Tichelaar, F.; Visser, P.; Gonzalez-Garcia, Y.; Zandbergen, H.; Terryn, H.; Mol, J. M. C.
• Is Part Of: Journal of the Electrochemical Society. Volume 168:Issue 4(2021)
• Publication Date: 2021-04-16
• Subjects: Dealloying -- Cerium-based corrosion inhibitor -- Localized corrosion inhibition -- Aerospace aluminium alloys -- Analytical transmission electron microscopy -- Intermetallic particles; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/abf50d
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Cerium-based compounds have been studied for decades as non-toxic candidates for the protection of aerospace aluminium alloys (AAs) like AA2024-T3. However, the complex heterogeneous microstructure of these alloys has hindered a thorough understanding of the subsequent stages of corrosion protection provided by this class of inhibitors. Thus, this work is devoted to unravelling the interaction mechanisms of different intermetallic particles (IMPs) in AA2024-T3 with cerium nitrate at the nanoscopic scale. This has been fulfilled through detailed top-view and cross-sectional analytical TEM investigations along with electrochemical evaluations. In line with our recent findings, we here report dealloying of IMPs as the main factor governing the rate of local cerium precipitation in contrast to micro-galvanic corrosion between IMPs and the surrounding matrix. Furthermore, we discuss a connection between the electrochemical response of the AA2024-T3 system and the morphological and compositional evolutions of individual IMPs including Al2 CuMg, Al2 Cu, Al7 Cu2 Fe(Mn) and Al76 Cu6 Fe7 Mn5 Si6 at different stages of a 96-h exposure.