| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 8026199 | Surface and Coatings Technology | 2015 | 13 Pages |
Abstract
The formation of a trivalent conversion coating on aluminium has been investigated using analytical electron microscopy, atomic force microscopy, ion beam analysis, glow discharge optical emission spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The coating is shown to comprise a chromium- and zirconium-rich outer layer and an aluminium-rich inner layer. Zirconium and chromium are present in chemical states consistent with ZrO2, ZrF4, Cr(OH)3, Cr2(SO4)3, CrF3 and CrO3 or CrO42Â â. However, negligible amounts of Cr(VI) species occurred in coatings formed in de-aerated solution. Electrochemical impedance spectroscopy revealed that the inner layer provides the main corrosion protection during short-term tests in 0.1Â M sodium sulphate solution at room temperature.
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Nanotechnology
Authors
J.-T. Qi, T. Hashimoto, J.R. Walton, X. Zhou, P. Skeldon, G.E. Thompson,