Alternative Corrosion Protection Pre-treatments for Aluminium Alloys
Aluminium alloys are extensively used in space programs for both structural and non-structural applications. As well known, the corrosion resistance of these alloys is quite limited and anticorrosion treatment is needed.
The most used treatment currently used for improving the corrosion resistance of aluminium alloys are usually chromate (CrVI-based) conversion coatings (CCC). Due to the high environmental impact of these compounds, the REACH Regulation of the European Union decided to limit/restrict the use of hexavalent chromium. A sunset date of mid-2017 has been already set.
For the time being many chromate-free alternative products are available but they have found to be significantly inferior in terms of corrosion protection performances with respect to the chromate options. In this regard there is a great need to develop high performance hexavalent chromium-free anti-corrosion coatings with low environmental impact and conformity with the EU regulations.
