Dealloying-driven local corrosion by intermetallic constituent particles and dispersoids in aerospace aluminium alloys

Journal article (2020)

Authors

A. Kosari (OLD) MSE-6
F.D. Tichelaar QN/Afdelingsbureau , Kavli institute of nanoscience Delft
P. Visser Akzo Nobel
H.W. Zandbergen Kavli institute of nanoscience Delft, QN/Zandbergen Lab
H.A. Terryn Vrije Universiteit Brussel
J.M.C. Mol (OLD) MSE-6
Research Group
(OLD) MSE-6
Copyright: © 2020 A. Kosari, F.D. Tichelaar, P. Visser, H.W. Zandbergen, H.A. Terryn, J.M.C. Mol
DOI: https://doi.org/10.1016/j.corsci.2020.108947
More Info
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Published Date

2020

Language

English

Research Group

(OLD) MSE-6

Abstract

Nanoscopic characterization of heterogeneous intermetallic particles (IMPs) which microstructurally and compositionally evolve during local corrosion is crucial in unravelling the mechanisms and sequence of initial and local corrosion events. Herein, we study site-specific initiation events focused on microscopic constituent intermetallic compounds and nanoscopic dispersoids in AA2024-T3 at the nanoscale using a combined quasi in-situ and ex-situ analytical TEM approach. Our findings show a dealloying-driven local corrosion initiation at the studied IMPs that have been considered as cathodic phases traditionally. Besides, local degradation which is a result of galvanic interactions between dealloyed regions of IMPs and their adjacent alloy matrix is largely governed by the intrinsic electrochemical instability of intermetallic compounds.