The main result of the Cr Free REAL project is a green, innovative, REACH compliant process that assure the removal of the oxide layers (anodised and conversion coatings with and without Cr(VI)) from five types of aluminium alloys. The high performance of the Cr free process was proven at lab and semi-industrial scale for samples with complex geometries.
The main technical achievements of the Cr Free REAL project are:
• Development of an innovative, environmentally friendly, Cr(VI)-free process for oxide layers removal with acidic stripping agents enhanced with functional additives
• A deep understanding of the mechanisms of the stripping processes (oxide layer removal, attack of the substrate and inhibition of such attacks) and the effect of various process parameters during the stripping process
• A universal, green process, suitable for substrates of various types of machined and cast aluminium alloys and for removal of Cr(VI)-free and Cr(VI)-based oxide layers
• A uniform removal of the oxide layers without attack on the substrate was achieved as a function of immersion time
• Cr Free REAL stripping process has reduced effects on recoated parts properties, showing good performance against corrosion for multiple cases
• A process that enables Cr(VI)-free green operation modes for re-working of out-of-specification oxide layer coatings in the production process and for ground-based repair and maintenance operations
• Generated knowledge could be furthermore developed and adapted to other industrial requirements
Project achievements were disseminated as oral presentations to various international conferences (e.g. EUROCORR, EUROMAT). A follow-up project is foreseen to further increase innovation TRL level.
The Cr Free REAL project acknowledged the funding received from H2020, Clean Sky 2 program: “The research leading to these results has received funding from the European Community’s H2020 for the Clean Sky joint technology initiative under grant agreement no. 831991”.
