Micro Arc Oxidation Coating Parameter-Property Relationship

Abstract

Micro arc oxidation coatings were produced on AA7075 (UNS A97075) substrates using various process parameters. The study aimed to improve the surface characteristics of the alloy. Thickness, hardness, and roughness measurements characterized the coatings. It was revealed that the coating thickness was directly related to the coating roughness. Various aluminum oxide (Al2O3) phases were detected in the coatings, and phase density differences were determined. Variations in the hardness of the coatings depended on the phase distribution, porosity, and presence of micro-cracks. Scanning electron microscopy investigations of the coating/substrate interface proved a simple and quick analysis of porosity. © 2021 NACE International. All rights reserved.