Active Mesostructured Particles produced by Aerosol incorporated in Sol-Gel coatings for corrosion protection of Aeronautical Aluminum alloys – AERO²

The necessity of being compliant with environmental regulations and in accordance with the new assembly technologies (large integral structures) is now more than ever an important driving force to replace existing protection schemes for aeronautics.
Development of alternatives is essential and timely because safe and efficient solutions have not yet been found.

To address this challenge, AERO² aims at designing new corrosion inhibitors-loaded mesostructured particles included in smart hybrid sol-gel coatings, for the protection of light aeronautical alloys.
This smart coating will be composed of 2 main elements:
• mesostructured particles loaded by corrosion inhibitors produced by aerosol process
• smart hybrid sol-gel matrix presenting both intermetallics inclusions of the alloy passivation and barrier properties and able to self-heal in case of injury.
The association of these inhibitors-loaded mesostructured particles and the smart matrix will provide a single multicomponent coating designed in the aim to prevent simultaneously the main factors (intermetallics of aluminum alloy, diffusion of Cl- anions, water and dioxygene), that originate corrosion of aluminum.

Sol-gel coatings are widely mentioned in literature as protection for metals because of their good barrier properties. Nevertheless, the introduction of nano-objects, like corrosion inhibitors, in such homogeneous matrix considerably modifies final properties (adhesion, corrosion resistance…) of the coating, not obviously in an improvement way. Up to now results obtained by active protective sol-gel coatings are not sufficient for highly-challenging aeronautical requirements (ie. life of aircraft is around 40 years).
AERO² targets to proof the concept of this global approach, which has never been considered. In addition, designing and processing by aerosol route, porous mesostructured particles which can be filled and/or functionalised with opportune groups or inhibitors are very challenging and still unexplored for corrosion protection and in particular in aeronautic fields. AERO² aims at bringing a breakthrough innovation to the protection schemes as well as contributing to set an innovative way to elaborate active protection against corrosion for light aeronautical alloys.

The approach proposed in AERO² is whole, from the design of nanocontainers active against corrosion (chemical nature and aerosol process), their introduction into coatings, to scaling-up for spraying applications. Moreover, AERO² aims at going from Technology Readiness Level 1 to 3. In order to reach these achievements, the AERO²’s consortium brings together all the necessary links. Indeed, EADS IW represents the link with final end-users (Airbus, Astrium, Eurocopter…) and has an expertise in such coatings for corrosion protection. LCMCP is expert on Sol-Gel material (coating and particles) and CIRIMAT on corrosion studies. Finally, PYLOTE already commercializes submicronic particles elaborated by aerosol process.

To go further, the product that will be developed in AERO² could also fit with different applications in various sectors such as automotive, naval, medicine…