Growth of plasma electrolytic oxidation coatings on Nb and corresponding corrosion resistance

Plasma electrolytic oxidation (PEO) coatings were formed, respectively in three silicate-based, phosphate-based and aluminate-based electrolytes on niobium, with the aim to explore the relationships between electrolyte composition, dielectric breakdown behavior and corresponding corrosion resistance. The initial growth stages of the anodic coatings were studied, and result shows that an impedance falling stage (from about 200 V to 400 V) starts...