Ceria embedded nanocomposite coating fabricated by plasma electrolytic oxidation on titanium

• Ceria embedded coatings showed superior corrosion and wear properties.
• Optimum concentration of nanoparticles for improved surface properties.
• Surface porosity affects wear and corrosion properties.
• High concentrations of nanoparticles does not lead to superior wear properties.
• Ceria nanoparticles are among good choices for PEO coatings.

In this study, wear and corrosion behaviors of PEO coatings on Ti substrate were evaluated. Ceria nanoparticles were added into PEO electrolyte as suspention. Rare earth elements and compounds are through environmental friendly and effective compounds. Effect of Ceria nanoparticles and their concentration was evaluated using SEM, FTIR, EDS, potentiodynamic polarization, EIS and pin on disk tests. In morphological investigations, it was revealed that with addition of 25 gr/L ceria nanoparticles, pores become filled and lowest surface roughness was achieved in this concentration. Corrosion potential of coatings moves toward noble potentials with addition of ceria nanoparticles and also corrosion current density decreases. Wear rate of coatings also decreased with ceria nanoparticle addition, but optimum properties depend on surface conditions. Wear rate decrease from 3.4 μg/N.m to 0.7 μg/N m by addition of 25 gr/L ceria nanoparticles.