FORMATION AND CHARACTERISATION OF CHROMATE-FREE CONVERSION LAYERS ON 5556 ALUMINUM ALLOY

The processes of applying cerium and titanium, zirconium-containing coatings to 5556 aluminum alloy have been developed. It is established that the developed passivation coatings applied on aluminum alloy parts for corrosion resistance and protective ability are comparable with chromate coatings. It was revealed that, unlike chromate coatings, the developed cerium and titanium, zirconium-containing coatings withstand the thermal shock without degrading of characteristics. It was established that the thickness of cerium-containing coatings is about 300 nm, and that of titanium, zirconium-containing coatings is about 100 nm.