Fabrication and characterization of haemocompatible TiO2 films by thermal and Anodic Oxidation Techniques

M. L. VERA; A. E. ARES; M. R. ROSENBERGER; C. E. SCHVEZOV

Rosario, Santa Fé, Argentina.

Workshop; PRIMER TALLER DE ÓRGANOS ARTIFICIALES, BIOMATERIALES E INGENIERÍA DE TEJIDOS, BIOOMAT 2009; 2009

Sociedad Latinoamericana de Biomateriales, ngeniería de Tejidos y Órganos Artificiales (SLABO)

A protective titanium dioxide (TiO2) film covers the surface of the Ti and its alloys in ambient conditions. This natural oxide is 2 to 7 nm thick, and it is one of the principal responsible for the success as an implantable material. Thicker TiO2 films can be produced on Ti-6Al-4V alloy as substrate by thermal and anodic oxidation. In this study, TiO2 films produced by thermal and anodic oxidation techniques are compared. TiO2 films produced by thermal oxidation were growth on Ti-6Al-4V substrates in air atmosphere at 500 and 600°C during different times (0.5, 1, 2 and 24 hour). TiO2 films produced by anodic oxidation technique used a 1M H2SO4 solution as electrolyte where Ti-6Al-4V substrates were submerged and treated at different voltages (from 10V to 100V) during 1 min. The surface characterization was performed by optical and scanning electron microscopy, and by X-ray diffraction (XRD) operated with glancing angle geometry with an angle of incidence of 1°. Films of different colours of interference were obtained. The oxide layers produced thermally at short times (up to 1h) and anodically at low voltages (up to 50V) were smooth. At long times and voltages larger than 50V coatings became porous. Crystalline phases of TiO2, anatase and rutile, were obtained by thermal treatment and at high voltages of the anodic treatment or by a combination of both, thermal treatment of amorphous oxides produced anodically at low voltages. Each of these morphologies and structures of the coatings are suitable to different biomedical applications and devices.