Preparation, corrosion resistance and hemocompatibility of the superhydrophobic TiO2 coatings on biomedical Ti-6Al-4V alloys

Abstract In this paper the micro-arc oxidation (MAO) technique and subsequent superhydrophobic treatment were applied to fabricate the superhydrophobic TiO 2 coatings on biomedical Ti-6Al-4V alloys. The surface morphology, surface roughness, water contact angle, corrosion resistance and hemocompatibility of the MAO and superhydrophobic samples were investigated. The results showed that the single anatase TiO 2 coating was formed on the surface Ti-6Al-4V alloy with rough and porous micrometer-scale structure. The low surface energy film was grafted on the surface of the TiO 2 coating by self-assembling reaction during the hydrophobic treatment process, which resulted in the formation of superhydrophobic surfaces with the water contact angle of 153.39°. It was found that the corrosion resistance of the superhydrophobic samples increased by one order of magnitude compared to those of the uncoated Ti-6Al-4V alloys. The hemolysis ratio and platelets adhesion characteristics of the Ti-6Al-4V alloys were also improved greatly through the MAO treatment and subsequent superhydrophobic treatment. Especially, no platelet could be observed on the surface of the superhydrophobic samples. Therefore, the superhydrophobic TiO 2 coatings of Ti-6Al-4V alloys with higher hemocompatibility would show great promise in their potential blood-contacting applications.