Corrosion Behavior of Fe 2 O 3 /Alumina Layer Produced by Plasma Electrolytic Oxidation of 6061 Al Alloy.

This study looked into the influence of iron nitrate (Fe(NO₃)₃ on the corrosion behavior of a 6061 Al alloy treated by a plasma electrolytic oxidation coating (PEO). PEO coatings were fabricated on Al alloy samples under AC conditions utilizing an alkaline-aluminate electrolyte containing 0 and 5 gr of Fe(NO₃)₃. Surface examination demonstrated that some Fe₂O₃ particles were effectively integrated into the coating layer produced in a solution containing Fe(NO₃)₃. In addition, the porosity and the size of micropores made due to plasma activity were significantly reduced after the PEOO treatment of the 6061 Al substrate in an electrolyte containing Fe(NO₃)₃. Accordingly, the coating formed in the electrolyte with Fe(NO₃)₃ exhibited superior corrosion resistance to that treated in the electrolyte without Fe(NO₃)₃. [ABSTRACT FROM AUTHOR]