Corrosion performance of Fe-Al intermetallic coatings in 1.0 M NaOH solution

Three different particle sizes were used to deposit FeAl and Fe3Al intermetallic coatings by thermal spray techniques: flame spraying and HVOF (High Velocity Oxygen Fuel). Coatings were characterized by SEM (scanning electron microscopy) and their characteristics are presented considering particle size and deposition process employed. Coatings performance was evaluated using electrochemical test in a solution of 1.0 M NaOH at room temperature. It was observed that deposition technique used and particle size influences the electrochemical performance of coatings. Coatings showed no significant variations in their current densities, but were one order of magnitude higher than those of base alloys, the corrosion potential of coatings were similar regardless of the particle size and more active than their alloy base.