Enhanced long-term corrosion protection of 2A14 aluminum alloy: Hybrid effect of micro-arc oxidation coating and cerium based conversion treatment

The novel cerium based conversion (CeC) treatment was performed on 2A14-T3511 aluminum alloy micro-arc oxidation (MAO) coatings with thickness of 15 μm and 30 μm, respectively. The sealing effect of CeC treatment on MAO coatings and the chemical composition of the sealant were characterized. The influence of coating structure on the deposition of cerium compounds was systematically discussed. Additionally, long-term corrosion behavior was investigated using electrochemical methods. The results showed that CeC treatment significantly improved the long-term corrosion protection of MAO coatings. This is attributed to the physical sealing and chemical corrosion inhibition of the Ce based deposits.