In-situ nanoscopic observations of dealloying-driven local corrosion from surface initiation to in-depth propagation
Ali Kosari (TU Delft - (OLD) MSE-6)
H. W. Zandbergen (TU Delft - QN/Zandbergen Lab, Kavli institute of nanoscience Delft)
F. D. Tichelaar (TU Delft - QN/Afdelingsbureau, Kavli institute of nanoscience Delft)
P Visser (Akzo Nobel)
P. Taheri (TU Delft - (OLD) MSE-6)
H. Terryn (Vrije Universiteit Brussel)
J. M.C. Mol (TU Delft - (OLD) MSE-6)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
Dealloying is involved in materials science responsible for fabrication of nanoscale structures beneficially but for corrosion degradations detrimentally. Detailed understanding related to the latter is critical for designing corrosion-resistance alloys and dedicated inhibition systems. Thus, direct nanoscopic observations of nano-structural and compositional evolutions during the process are essential. Here using liquid phase-transmission electron microscopy (LP-TEM), for the first time, we show dynamic evolution of intricate site-specific local corrosion linked to intermetallic particles (IMPs) in aerospace aluminium alloys. To thoroughly probe degradation events, oxidation direction is controlled by purposefully masking thin specimens, allowing for observing top-view surface initiation to cross-sectional depth propagation of local degradations. Real-time capturing validated and supported by post-mortem examinations shows a dealloying-driven process that initiates at IMPs and penetrates into the depth of the alloy, establishing macroscopic corrosion pits. Besides, controversial mechanisms of noble-metal redistribution are finally elucidated.
help_outline