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

Friction

M. L. Rodríguez-Méndez¹  C. Garcia-Hernandez²  C. Salvo-Comino²  V. Amigó Borrás³  F. Martin-Pedrosa⁴  C. Garcia-Cabezón⁴  R. Bayón⁵ 

[1] BioecoUVA Research Institute, Universidad de Valladolid, 47011, Valladolid, Spain;Group UVASENS, Escuela de Ingenierías Industriales, Universidad de Valladolid, 47011, Valladolid, Spain;Group UVASENS, Escuela de Ingenierías Industriales, Universidad de Valladolid, 47011, Valladolid, Spain;Instituto de Tecnología de Materials, Univesitat Politécnica de Valencia, 46022, Valencia, Spain;Materials Engineering, E.I.I., Universidad de Valladolid, 47011, Valladolid, Spain;BioecoUVA Research Institute, Universidad de Valladolid, 47011, Valladolid, Spain;Tribology Unit, Fundación IK4-Tekniker, 20600, Eibar, Spain;

关键词: Ti-based alloys;    corrosion;    tribocorrosion;    surface modification;   

DOI  :  10.1007/s40544-020-0480-2

来源: Springer

【 摘 要 】

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.

【 授权许可】

CC BY