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This study aims to investigate the effect of post-treatment on anti-corrosion performance of Al coating on the surface of Ti-6Al-4V (TC4) fastener.

The Al coatings with different layer structures were prepared on TC4 by middle-frequency and direct-current combined magnetron sputtering. The cross-sectional morphology and surface roughness of coatings were characterized by scanning electron microscope and atomic force microscope. The corrosion resistance was evaluated by electrochemical method. The monolayer coating was post-treated by Alodine chemical conversion, Ar⁺ bombardment and a combination of two methods above.

The results show that the interfaces in bilayer and trilayer coatings reduce the defects. Ar⁺ bombardment reduces the corrosion current density, and Alodine chemical conversion leads to a higher pitting corrosion potential. The combined post-treatment has the highest polarization resistance.

The corrosion resistance of the Al coating is enhanced as the layer quantity increases. The combination of two post-treatments, Ar⁺ bombardment and Alodine chemical conversion, could achieve an overall improvement in corrosion resistance of Al coating.

In the present work, the protective properties of inhibitive pigments in two epoxy‐primers against corrosion of the aluminium alloy 2024T3 in marine atmosphere were investigated, the first containing SrCrO₄ and the second Zn₃(PO₄)₂. Potentiostatic polarisation and impedance measurement methods were utilised to evaluate, both the spontaneous onset of defects on coated samples and the propagation of a small artificial defect of known dimension applied since the beginning of the test on each sample, during 24 months of exposure to the marine atmosphere. These techniques enabled a quantitative evaluation of the protective efficiency of the two primers to be made, and for the effects of the surface pre‐treatments of the metallic substrate to be investigated.

Repainting aircraft is a laborious and time‐consuming process, involving stripping, surface preparation and then painting. It is possible to distinguish two different systems for aircraft re‐painting, owing to their prime application area, referred to as the “European System” and the “USA System”. Examines these two systems and discusses the health and environmental aspects, along with their level of corrosion protection. Examines the properties of a new binder system, referred to as the KETAC‐System. As a result of the formulation of this new binder a new primer system was developed. The development of this primer , known as Aviox CF Primer, was carried out in close co‐operation with KLM Royal Dutch Airlines, the results of which are reviewed.