Abstract:
Plasma Electrolytic Oxidation (PEO) has emerged as a versatile surface engineering
technique for producing thick, adherent, and multifunctional ceramic coatings on light
metals such as aluminum, magnesium, and titanium alloys. This presentation provides an
overview of the fundamental mechanisms governing PEO coating formation, with
particular emphasis on plasma-assisted electrochemical reactions, microarc discharges,
and the resulting hierarchical microstructures. The relationships between processing
parameters, coating architecture (porous outer layer and dense inner barrier layer), and
functional properties, including hardness, wear resistance, corrosion protection, and
dielectric performance, are discussed. Recent advances in tailoring coating composition
through electrolyte design and post-treatment strategies are highlighted, enabling
enhanced performance for demanding environments. Industrial applications of PEO
coatings in sectors such as oil and gas, marine/offshore, aerospace, and biomedical
engineering are reviewed, demonstrating their capability to improve component
durability and reliability. Key challenges, including process scalability, energy efficiency,
and coating uniformity on complex geometries such as particle surface and inner walls of
conduit structures, are also addressed. Finally, future directions toward hybrid coatings
and smart functional surfaces are outlined, positioning PEO as a promising technology
for next-generation industrial applications.