Assessment of hydrophobic and anticorrosion properties of composite silane-zeolite coatings on aluminum substrate

The effect of matrix compounds on the behavior of silane-zeolite composite coatings on a 6061 aluminum alloy was evaluated by electrochemical test performed at long immersion time in 3.5% NaCl solution. It was observed that silane chains influence the hydrophobic behavior and the electrochemical performances of the zeolite-based composite coating. All composite coatings showed a long-term protection action in 3.5% NaCl solution. The use of silane compounds with long alkyl chain or with bi-hydroxyl groups made it possible to obtain electrochemically stable coating during long immersion time. Best results have been obtained with a multicomponent silane mixture (short and long molecular chains).