Influence of Surface Preparation on Morphology of Self-organized Nanotubular Oxide Layers Developed on Ti6Al4V Alloy

An ordered nanostructured surface of biomedical implants facilitates the enhancement of their osseointegration. It has been demonstrated that TiO2 nanostructures (nanotubes/nanopores with 15-100 nm diameter) strongly promote bone cells adhesion, proliferation and differentiation. Present paper presents our results on development of ordered nanostructured TiO2 layer on the surface of two phase (α+β) Ti6Al4V alloy by using electrochemical anodization in H3PO4/HF electrolytes. Our results show a successful deposition of oxide layers exhibiting requested morphology for a proper biological response, regardless of initial flat surfaces manufacturing process (polishing, conventional milling, sand blasting and acid etching,) and their initial roughness (Ra = 0.05-2.3 μm). On polished surfaces (Ra = 0.05 μm) and milled surfaces (Ra = 0.5 μm) we deposited well defined, self-ordered, nanotubular TiO2 with internal diameter in the range of 50-100 nm. On sand blasted and acid etched surfaces (Ra = 2.3 μm) we developed nanoporous structures having pores diameter of 25-65 nm.