MAO-Prepared Hydroxyapatite Coating on Ultrafine-Grained Titanium
The equal channel angular pressing (ECAP) results in ultrafine-grained (~200–500 nm) Ti with superior mechanical properties without the harmful alloying elements, which is beneficial for medical implants. To improve the bioactivity of Ti surface, Ca/P-containing porous titania coating were prepared on the ultrafine-grained Ti and coarse-grained Ti by micro-arc oxidation (MAO) in Ca/P based solution. The phase identification, thickness, composition and morphology of the coatings were analyzed. The amounts of Ca, P and Ca/P ratio of the MAO coating formed on ultrafine-grained Ti were higher than those for coarse-grained Ti samples. Hydroxyapatite and α-Ca3(PO4)2 phases appeared in MAO coating formed on ECAP-treated Ti with increasing reaction time of 20 min (E20). Incubated in simulated body fluid within 2 days, bone-like apatite was completely formed on E20 surface, as evidenced of preferable bioactivity.
Jian-Feng Nie and Allan Morton
M. Qi et al., "MAO-Prepared Hydroxyapatite Coating on Ultrafine-Grained Titanium", Materials Science Forum, Vols. 654-656, pp. 2168-2171, 2010