Enhancement Technique of Corrosion Protection for Aluminum Alloy Used in Ships

In marine environments, traditional organic coatings are generally used in ships for corrosion protection of aluminum alloys. However, a problem was brought forward during ship maintaining period, i. e., the organic coatings were not enough to control aluminum pitting corrosion under coatings. An enhancement technique of corrosion protection for aluminum alloy was investigated by adding a layer of chromate-free conversion coating between aluminum alloy substrate and organic coatings. The SEM and EIS experimental results showed that the chemical conversion coating had compact structure and exhibited good corrosion protection performance, and thus enhanced the anti-corrosion capability of aluminum alloy used in ships.