[In vitro bioactivity of HA/Ti6Al4V composite implant fabricated by RF magnetron sputtering]

This is a report on the research of HA/Ti6Al4V composite implants that were successfully fabricated by radio frequency magnetron sputtering (RF-MS) technique. The mechanism and bioactivity of these implants immersed in simulated body fluid (SBF) were investigated. Changes in surface morphology, interfacial bond state, crystal structure and phase composition of HA coating before and after immersing in SBF were characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Results indicate that a new substance on the surface of HA implant coatings produces accompanying with the dissolution of coatings. The substance is bone-like apatite containing CO3(2-) and lacking of Ca2+. Its ratio of n(Ca)/n(P) is about 1.56. This substance has very small grain size and similarly amorphous structure. Its structure and composition are similar to those of natural bone. Thus, it has good biocompatibility and bioactivity.