Influence of oxysalts on plasma electrolytic oxidation (PEO) of titanium performed in NaOH solution for corrosion protection
Year: 2025
Type: article
Abstract: The present paper discusses the influence of oxysalts, namely tungstate, zirconate, and silicate, on the plasma evolution during the PEO process on titanium, performed in a sodium hydroxide solution. The morphology, thickness, and corrosion resistance strongly depend on the specific type of oxysalts added to the electrolytic bath. Scanning electron microscope (SEM) imaging reveals that zirconate promotes the production of thicker coatings than tungstate, while when silicate is used more porous oxides with a very rough morphology are obtained. Coatings processed with silicate also show a high level of amorphism, while the other types of oxides are mainly crystalline, as highlighted by X-ray diffraction (XRD) testing. The anti-corrosive performance is evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) analyses performed in a hot sulfuric acid solution. All the PEO samples display higher polarization resistances and lower corrosion current densities than the bare titanium showing an improved corrosion resistance.
Source: Materials Today Communications
Authors: Federica Ceriani, Luca Casanova, Luca Paterlini, Irene Costa, Marco Ormellese
Institution: Politecnico di Milano
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,830
OpenAlex ID: W4409604919