Supervisor: prof. Dušan Galusek, FunGlass, Slovakia
Partner research institution: Consejo Superior de Investigaciones Cientificas, Spain; supervised by prof. A. Duràn, Dr. Yolanda Castro
The project proposes to investigate the preparation of integrated self-healing systems for light metal alloys based on anodic, organic, hybrid and inorganic layers. These systems will be able to provide active behavior suppressing corrosion processes near defects combining different repairing mechanisms which will be progressively activated, to provide a prolonged life time.
Cr (VI) -based compounds represent the state of the art in corrosion protection of aluminum alloys in the aerospace field. The self-healing ability, present in the chromate conversion, is superior to any other protection system currently available, but European directives strongly limit the use of Cr (VI) for its health and environmental toxicity.
This project proposes to replace chromate conversion coatings by developing systems that combine different self-healing mechanisms in the same system, joining different layers that constitute a corrosion resistant architecture.
The project considers the development of anodic oxide layers for light alloys based on the incorporation of encapsulated corrosion inhibitors into the oxide layer and thus leading to self-healing ability. Then, a sol-gel coating will be deposited onto anodic films as an alternative sealing method to enhance the corrosion performance of these coatings. The infiltration of the anodic films using different sol-gel sols will be also considered.
In the sol-gel part, the development of novel inorganic films combining organic and/or inorganic inhibitors as salts (cerium or rare earth) will be considered. These inhibitors are activated by environmental parameters promoting the self-healing mechanisms effect; e.g. Glass-like CexOy coatings incorporating CexOy NPs. On the other hand, hybrid organic-inorganic coatings will be developed incorporating inhibitors with different release kinetics and activation mechanisms. In all cases, improve the density and adhesion to metals and paints and self-healing ability will be the principal goals.
The project involves the optimization of compositions and synthesis conditions together with the characterization of the integrated systems. The following general tasks will be carried out:
- To develop anodic oxide layers incorporating corrosion inhibitor.
- To develop effective inorganic, hybrid and organic coatings with self-healing ability for light Al and Mg alloys;
- To develop integrated self-healing coating systems, showing superior self-healing performance (activity, stability, long life protection).
- Characterization of integrated self-healing systems (thickness, microstructure, adhesion properties, self-healing functionality of coatings, electrochemical and corrosion resistance tests…)
- L. Paussa, N. C. Rosero Navarro, F. Andreatta, Y. Castro, A. Duran, M. Aparicio, L. Fedrizzi, Surface and Interface Analysis 42 (2010) 299-305
- C. Rosero-Navarro, Y. Castro, M. Aparicio, A. Durán, Spanish Patent P200930982-CSIC, PCT/ES2010/070726
- C. Rosero-Navarro, S. A. Pellice, A. Durán, M. Aparicio. Corr. Sci. 50 (2008) 1283–1291.
- D. López, N. C. Rosero-Navarro, J. Ballarre, A. Durán, M. Aparicio, S. Ceré, Surface & Coatings Technology, 202 (2008) 2194–2201