Functionalization of an experimental Ti-Nb-Zr-Ta alloy with a biomimetic coating produced by plasma electrolytic oxidation

This study developed an experimental quaternary titanium (Ti) alloy and evaluated its surface properties and electrochemical stability. The viability for a biofunctional surface treatment was also tested. Ti-35Nb-7Zr-5Ta (wt%) alloy was developed from pure metals. Commercially pure titanium (cpTi) and Ti-6Al-4V were used as controls. All groups had two surface conditions: untreated (machined surface) and modified by plasma electrolytic oxidation (PEO) (treated surface). The experimental alloy was successfully synthesized and exhibited β microstructure. PEO treatment created a porous surface with increased roughness, surface free energy, hardness and electrochemical stability (p < 0.05). For the machined surfaces, the Ti-Nb-Zr-Ta alloy presented the lowest hardness and elastic modulus (p < 0.05) and displayed greater polarization resistance relative to cpTi. Only PEO-treated cpTi and Ti-Al-V alloys exhibited anatase and rutile as crystalline structures. The β experimental Ti-Nb-Zr-Ta alloy seems to be a good alternative for the manufacture of dental implants, since it presents elastic modulus closer to that of bone, feasibility for surface treatment, electrochemical stability and absence of toxic elements77010381048FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2016/11470-6; 2017/01320-0This work was supported by the São Paulo State Research Foundation (FAPESP), Brazil (grant numbers 2016/11470-6 and 2017/01320-0). The authors express their gratitude to Jamille Altheman for her contribution and support at the Laboratory of Technological Plasmas at Univ. Estadual Paulista (UNESP), to Dr Richard Landers and Rita Vinhas from the University of Campinas (Institute of Physics Gleb Wataghin) for providing the XPS facility, to Dr Mathew T Mathew from the University of Illinois at Rockford (College of Medicine at Rockford, Department of Biomedical Sciences) for the donation of the electrochemical cell, and to the Brazilian Nanotechnology National Laboratory (LNNano) at the Brazilian Center of Research in Energy and Materials (CNPEM) for the XRD facilit