Synergistic corrosion protection for magnesium alloys – SYNPROMAG

The lightening of the aircraft structure is one of the strong lines of research for reducing the consumption of kerosene and reducing CO2 emissions. With a density one-third lower than that of aluminum, magnesium is the lightest of structural metals. The low corrosion resistance is a major lock for wider use of magnesium alloys in aeronautics.
Hexavalent chromium (Cr VI) treatments are currently the most effective to protect magnesium alloys from corrosion. As Cr VI is classified as CMR (Carcinogenic, Mutagenic and Reprotoxic) by the European REACH regulation, it is imperative to develop alternatives to chromium based treatments.
The SYNPROMAG project aims to improve the service life of magnesium alloys in corrosive environments by proposing the development of innovative self-repairing coatings integrating active nano-objects.
The technological solutions developed in the SYNPROMAG project will be respectful of the new international regulations, in particular REACH. Unlike most previous or ongoing programs about corrosion protection programs for light alloys, the nano-objects developed in SYNPROMAG will not be derived from soft chemistry processes. The active objects will be prepared by bottom up approach in aqueous phase.
The originality of the concept developed in SYNPROMAG is based on the structure of synthesized nano-objects that will allow a synergy of actions at two levels:
- in terms of active properties anticorrosion by combining two corrosion inhibitors acting according to different modes of action in the same object
- by the multifunctional nature of the developed nano-objects: wear resistance, barrier properties and anti-corrosion active properties (controlled release of corrosion inhibitors).

The SYNPROMAG consortium consists of two complementary laboratories (MAPIEM and CIRIMAT) as well as an SME (MAPAERO), expert in the development of high-tech paints for aeronautics.