Graded surface structure of bioactive Ti-6Al-4V alloy prepared by chemical treatment

摘要

Ti-6Al-4V alloy can be subjected to NaOH and heat treatments to induce bioactivity on its surface. An Al- and V-free amorphous sodium titanate, which was integrated with the alloy substrate by a graded structure through titanium oxide, was formed in situ on the alloy by the NaOH and heat treatments. When exposed to a simulated body fluid, the surface sodium titanate transformed into a hydrated titania via Na~+ ions release to spontaneously induce a bonelike apatite formation on the surface of alloy. In this process, the graded structure of sodium titanate developed one in which the apatite on the top surface gradually changed into interior alloy substrate through hydrated titania and titanium oxide. This graded structure is believed to provide a strong integration of the alloy to a bone through the apatite layer in the body.