Influence of Surfactants on Microstructure and Properties of MAO Coated on Aluminum Alloy in Marine Construction

The ceramic oxide coatings on aluminum alloys for marine construction were formed through micro-arc oxidation (MAO) process with CTAB and SDBS surfactants in the original electrolyte solution. The composition, structure and some properties such as tribological behaviour and corrosion of alumina coatings were studied with different SDBS concentration varying from 0 to 0.2g/L (0,0.05,0.1,0.2g/L) in the electrolyte. The results show that the concentration of SDBS surfactant greatly influences the properties of MAO coating. The alumina coating surface becomes denser and thicker by adding SDBS surfactant in the electrolyte. Besides, the optimum concentration of the SDBS surfactant in the electrolyte to achieve the ceramic coating with a desirable thickness and consequently a desirable corrosion performance is 0.1 g/L.