Sol-gel derived bioactive hydroxyapatite/titania composite films on Ti6Al4V

摘要

The composite films consisting of the titania gel impregnated with hydroxyapatite (HAP) submicron particles were prepared on commercial Ti6A14V plates processed by a sol-gel route. HAP powders were synthesized based on wet chemical precipitation method with Ca(NO_3)_2 centre dot 4H_2O and (NH_4)_2HPO_4 as starting reagents. After being calcined at 900 deg C, HAP powders were ultrasonically scattered in ethanol to produce HAP sol. The titania sol was prepared using titanium (IV) isopropoxide {Ti[OCH(CH_3)_2]_4} as precursor. Both the titania sol and the HAP/titania mixture were sequentially spin-coated on the substrates and calcined at various temperatures. The characteristics and mechanical adhesion of the composite films were investigated. The results show that the as-prepared films are dense, homogeneous, well-crystallized, and there is a good interfacial adhesion between the film and the substrate. The in vitro bioac-tivities of these films were discussed based on the analysis of the variations of Ca and P concentrations in the simulated body fluid and their surface morphologies against immersion time.