Electrochemical Evaluation of MgO-CeO 2 Coatings on AA6066 Aluminum Alloy by MOCVD

The corrosion inhibition of AA6066 aluminum alloy due to the addition of MgO-CeO2 thin films using MOCVD has been investigated. The structure and morphology of the deposited coatings were also investigated on both polished quartz and AA6066 aluminum alloy substrates. The results from the different coating conditions show that under the best experimental conditions (Tp=230 ºC, Tsus=505 ºC and tdep=120 min), uniform and crack-free coatings with a mixture of oxides forming the film were obtained. The particle size of these coatings ranged from 130 nm to 1 µm with different morphologies according to the substrate. The electrochemical behavior of the MgO-CeO2 coatings caused a displacement to the cathodic direction due to the presence of an important amount of magnesium oxide; however, the passive film presented a truly protective nature in comparison with that of bare aluminum and those reported in the literature.