Aluminium and Magnesium Alloys Green Innovative Coatings

Project Information

ALMAGIC

Grant agreement ID: 755515

DOI

10.3030/755515

Project closed

EC signature date 12 April 2017

Start date 1 June 2017

End date 31 May 2019

Funded under

• SOCIETAL CHALLENGES - Smart, Green And Integrated Transport

Total cost

€ 999 526,25

EU contribution

€ 999 526,25

Coordinated by

FUNDACION CIDAUT
Spain

Periodic Reporting for period 1 - ALMAGIC (Aluminium and Magnesium Alloys Green Innovative Coatings)

Reporting period: 2017-06-01 to 2019-05-31

Summary of the context and overall objectives of the project

For decades, the aerospace industry has been, and still is, relying on hexavalent chromium-based (Cr(VI)) compounds (chromates) as active corrosion inhibiting material for the corrosion protection of the structures. Unfortunately, these hexavalent chromium compounds are toxic and have been shown to be carcinogenic. Chromates are among the current chemicals for which industrial users must find substitutes or seek authorisation from EU regulatory authorities to continue to use them.
The ALMAGIC project, "Innovative Green Coatings of Aluminium and Magnesium Alloys", has focused on solving this problem by validating the innovative alternatives developed to chromium(VI) coatings for aluminium and magnesium alloys. ALMAGIC has ensured that the solutions developed comply with the REACH regulation, while meeting all the quality standards of the aerospace industry.
The ALMAGIC proposal has pursued the definition and development of new surface treatments without chromium (VI) in their composition to replace the coatings currently used in lightweight aerospace engine materials. Efforts have focused on obtaining the highest quality of coatings developed in accordance with the requirements of the aerospace industry. The AMS2473 quality standard has been used as a reference. In addition to the corrosive behaviour of free chromium coatings, their electrical and mechanical properties (fatigue), as well as their paintability, have been analysed.
Finally, ALMAGIC has included as an added value the performance of corrosion tests on paints through the performance of the following specific aerospace tests on painted specimens: NSST (according to ASTM B-117); QCT condensation test (according to ISO 6270); filiform corrosion test (according to EN 3665); and conical mandrel (according to ASTM D522). This gives ALMAGIC the advantage of validating the alternatives developed to Chromium(VI) treatments far beyond what is required by the call, and demonstrating the value of the solutions developed to be applied by the aerospace industry.

At the end of the ALMAGIC project it can be concluded that all the scientific and technical objectives set at the beginning of the project have been achieved. In addition, very promising chromium-free coatings have been found for each of the alloys studied.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

- • WP1 Management has overseen the work flow, organizing meetings and web conferences when needed and working with the Work Package Leaders (WPLs) to ensure activities are carried out according to schedule.
- • WP2 was aimed at the development of Cr(VI)/Cr(III)-free conversion coatings for stand-alone magnesium and Mg-steel assemblies with similar or better performance than Cr(VI) Conversion Coatings (CC).
- • In WP3 the development of Cr(VI) free conversion coatings for aluminium has been carried out.
- • WP4 has focused on the development and characterization of different coating alternatives for acid anodization adapted to aluminium, with similar or better performance than that of Chromic AA.
- • WP5 has focused entirely on the validation according to the ASTMB117 quality standard of the three best chromium-free coatings of each WP (CC-Magnesium; CC-Aluminium and AA-Aluminium).

Coatings whose performance exceed, or at least equal, the performance of the current coatings used in the industry and that can be commercially exploited have been found for each of the cases studied: Mg-CC, Al-CC and Al-AA.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The success in the development of the activities proposed in the ALMAGIC contributes to the development of the alternative conversion coatings and acid anodisation alternatives to Chromium (VI) treatments leading to significant advantages related to the reduction in weight, associated to the use of lightweight materials (Aluminium and Magnesium, and the improvement of the protection of human health and the environment throught the elimination of the use of carcinogenic substances in our airplanes.
Much knowledge has been generated during the project that will enable further research on this topic, although higher TRL levels require larger experimental campaigns, and broader coatings development. The project has developed promising new coatings with anti-corrosion protection provided to run on the turbo-shaft engine withstanding environmental conditions. This may be exploited not only for this specific application in aviation, but also for the general development of other light alloy parts that may be useful in other applications and sectors.
Within the frame of Clean Sky 2, the research activities developed will contribute to the fulfilment of the objectives of the LPA program, orientated to the development, assessment and selection of integrative concepts and the development of breakthrough technologies to significantly increase the environmental performances of airplanes and air transport, bringing a key contribution in achieving the Single European Sky and ACARE environmental objectives.
Very interesting coatings have been found for each of the cases studied: Mg-CC, Al-CC and Al-AA for the magnesium alloy AZ31 and the aluminium alloy A2024, which can be developed for other alloys used in the aeronautics and automotive sectors. With these results, the ALMAGIC project presents promising environmentally friendly alternatives to the use of Chromium(VI), improving the impact of the EU coatings industry and complying with the REACH regulation.

img-20190516-115255.jpg

img-20190516-115238.jpg