Improvements in tribological and anticorrosion performance of porous Ti-6Al-4V via PEO coating


Medical implants manufactured using biomaterial Ti-6Al-4V exhibit some disadvantages. Its higher elastic modulus than that of natural bone can cause stress shielding problems. This can be avoided using Ti-6Al-4V with pores in the implant structure. However, poor corrosion and tribocorrosion behaviors are yielded because of the large area exposed to the medium. To mitigate both issues, coating technologies can be applied. The plasma electrolytic oxidation (PEO) process is a cost-effective process that has been used successfully in nonporous Ti alloys. In this study, two PEO coatings with different amounts of Ca/P are used. However, reports regarding their application in porous materials are scarce. The effects of PEO treatments on corrosion and tribocorrosion in Ti-6Al-4V powder metallurgy are analyzed herein. The porous materials provide an efficient surface for PEO coatings, as demonstrated via scanning electron microscopy (SEM) and atomic force microscopy (AFM), and the porosity of the substrates improved the adherence of the coatings. The corrosion resistance measured via electrochemical impedance spectroscopy confirmed the beneficial effect of the coatings, particularly for long exposure time. The lower roughness, small pore size, and more compact film observed in the PEO-Ca/P sample resulted in favorable tribological and corrosion properties.


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Financial support by Ministry of Education and Science (RTI2018-097990-B-I00) and the Junta de Castilla y Leon (VA275P18 and VA044G19) is gratefully acknowledged.

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Correspondence to C. Garcia-Cabezón.

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Cristina García Cabezón. She is a professor at the Engineers School of the University of Valladolid and and the co-head of the group UVASens, dedicated to the development of electrochemical sensors for the analysis of foods. She obtained a B.S.C. degree in Chemistry (U. Zaragoza, 1991) and obtained her Ph.D. degree in industrial engineering from the University of Valladolid (1998) where she is currently a professor at the Department of Materials Science.

For several years, her research was dedicated to the study of the electrochemical behavior of metals and metal nanoparticles and she became an expert in electrochemistry. Her investigation in the field of materials science and engineering is focused on corrosion, porous materials, and coatings. The materials in which these studies have been carried out are stainless steels, cobalt alloys, and titanium alloys.

In 2010, she joined the group UVASens, dedicated to the development of electrochemical sensors for the analysis of foods, where her skills in electrochemistry of metals and nanoparticles busted the research in the field of electronic tongues of the group. She has developed electrochemical sensors based on nanoparticles dedicated to the detection of antioxidants and the analysis in wines and milks. She is an author or co-author of 54 indexed articles (h-index 15). She has colaborations with several national and international groups. In particular, she is directing the collaboration with the group of Sensors of the I.P. Braganza (Portugal). She serves a referee of several journals related to electrochemistry (electrochimica acta, corrosion science, sensors, etc.). She reviews 12–15 papers per year. She regularly participates in contracts with industries.

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Garcia-Cabezón, C., Rodríguez-Méndez, M.L., Borrás, V.A. et al. Improvements in tribological and anticorrosion performance of porous Ti-6Al-4V via PEO coating. Friction 9, 1303–1318 (2021).

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  • Ti-based alloys
  • corrosion
  • tribocorrosion
  • surface modification