Preparation of self-healing hydrophobic coating on AA6061 alloy surface and its anti-corrosion property

Hydrolyzed fluorinated alkyl silane (FAS) containing well-dispersed fluorinated-decyl polyhedral oligomeric silsesquioxane (FD-POSS) was used to form a thin coating layer on AA6061 alloy. Its performance was evaluated by the electrochemical measurements and surface analysis technology. The FD-POSS/FAS film shifted the corrosion potential (Ecorr) of AA6061 alloy to a positive value, and suppressed significantly the anodic and cathodic corrosion reactions. Corrosion current density was decreased by one order of magnitude after FD-POSS/FAS coating treatment. The coating was hydrophobic with a water contact angle of 130°. It was highly transparent and had excellent stability and reasonable adhesion with AA6061. The coating also showed a remarkable self-healing ability to auto-repair from both chemical and physical damages. This self-healing FD-POSS/FAS coating may provide an effective protection toward aluminum alloys for power transmission applications.