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

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

Kosari, A. (TU Delft (OLD) MSE-6)
Tichelaar, F.D. (TU Delft QN/Afdelingsbureau; Kavli institute of nanoscience Delft)
Visser, P. (Akzo Nobel)
Zandbergen, H.W. (TU Delft QN/Zandbergen Lab; Kavli institute of nanoscience Delft)
Terryn, H.A. (Vrije Universiteit Brussel)
Mol, J.M.C. (TU Delft (OLD) MSE-6)

2020

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.

Aerospace aluminium alloys
Cross-sectional ex-situ TEM
Dealloying
FIB/SEM analysis
Pitting corrosion
Quasi in-situ TEM

http://resolver.tudelft.nl/uuid:14a039a4-679d-4ba9-8a16-f55e66daf161

https://doi.org/10.1016/j.corsci.2020.108947

0010-938X

Corrosion Science: the journal on environmental degradation of materials and its control, 177

Institutional Repository

journal article

© 2020 A. Kosari, F.D. Tichelaar, P. Visser, H.W. Zandbergen, H.A. Terryn, J.M.C. Mol