Abstract: HA(+ZrO₂+Y₂O₃)/Ti6Al4V composite coatings were fabricated successfully by radio-frequency magnetron sputtering RF-MS technique. The surface and interface morphologies, phase composition and chemical structure of the composite coatings were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Experimental results show that the amorphous coating deposited by RF-MS can be transferred into that with crystalline structure and restored OH- group by
post-annealing. The surface morphology of composite coatings is coarse
and uneven with the well-distributed concaves. The average diameter of
these concaves is in the range of 0.5～2.0μm, and the surface area of
these concaves is about 30%～40%. These concaves will greatly increase
the micro-surface area of coating. Interfacial tensile test indicates that
the interfacial bond strength between HA(+ZrO₂+Y₂O₃)/Ti6Al4V composite coating and substrate is 59.6MPa. Furthermore, the bond strength of HA(+ZrO₂+Y₂O₃)/Ti6Al4V composite coatings is enhanced with the increasing of sputtering power. Results of simulated body fluid (SBF) test indicate that a new substance on the surface of HA(+ZrO₂+Y₂O₃)composite coating will be produced after the composite coating immersed in simulated body fluid (SBF), this substance is bone-like apatite containing CO₃^2- group and has very small grain size and amorphous structure, its structure and composition are similar to those of natural bone. Thus, HA(+ZrO₂+Y₂O₃)/Ti6Al4V composite coatings have good biocompatibility and bioactivity.

Key words: HA(+ZrO2+Y2O3)/Ti6Al4V composite coatings, radio-frequency magnetron sputtering, bond strength, bioactivity