Corrosion and electrochemical behavior of aluminium treated with high-temperature pulsed plasma in CsCl–NaCl–NaNO3 melt

Dense protective layers of aluminium corrosion products, whose composition depends on the oxidation temperature, are formed on the surface of aluminium treated with high-temperature pulsed plasma (HTPP) without visible remelting and then held in a chloride–nitrate melt in conditions of anodic polarization. Modification of aluminium treated with HTPP changes the properties of 20 μm layer under its surface and the oxide layer formed by such treatment has different morphology: it consists of smaller crystals and so has the other protective properties as compared with aluminium untreated by plasma.

► Influence of plasma shot on corrosion behaviour of Al in chloride-nitrate melt.
► Nanostructured oxide film and oxide nanopowders 20 or 200 nm were obtained.
► Oxide film on plasma modified Al has better protective properties as to Al.
► At 900 K sodium-caesium aluminates forms instead of Al2O3 at 790–810 K.