Microarc Oxidation Coatings on Aluminum Alloy Drill Pipe

To improve service life, oxide coatings are deposited on the surface of aluminum alloy drill pipe for offshore platforms by microarc oxidation (MAO) technology. This work focused on an experimental study to determine the effect of cathode voltage on the morphology, phase composition, and corrosion performance of MAO coatings. It was found that the grains of the coatings become refined and smooth with increasing cathode voltage. Furthermore, the corrosion rates of the MAO coatings remarkably decreased with an increase in cathode voltage.