Ti-6Al-4V is widely used in dental implants and bone wounds. but it also has some disadvantages. For example, after implantation in human body, it releases toxic ions, such as V and Al. Lack of antimicrobial properties, adhesion to the surface of the bacteria in the human body is easy to cause infection. Studies have shown that coating TiN on the surface of titanium alloy is an effective method to improve its hardness and prevent harmful ions from precipitation. In this paper, the magnetron sputtering equipment is used to prepare Cu/TiN composite film on the surface of Ti-6Al-4V. The advantage of this method is that when the implant is worn out, copper ions are constantly precipitated out as an antimicrobial agent and play a bactericidal role. It is well known that implanting Ca or Mg on the surface of titanium alloy can also improve the biocompatibility of the implant effectively. Therefore, in this study, plasma immersion ion implantation (PIII) technique was used to inject equal amount of Mg²⁺ or Ca²⁺ into the surface of TiN/Cu composite membrane respectively to further improve the biological performance of the membrane. SEM, AFM and TEM were used to analyze the form of ions on the sample surface. The surface properties of the samples were evaluated by water contact Angle test, protein adsorption test and ion precipitation test. MC3T3-E1 cells were selected to analyze the cell proliferation and adhesion ability of the sample surface, and Escherichia coli was selected to analyze the bactericidal ability of the sample. The final study showed that the Cu/TiN composite membrane effectively improved the antibacterial activity of the samples, and in the case of the same implantation amount, the implantation of Mg²⁺ was more conducive to the improvement of the cell adhesion of surface compared with Ca²⁺.

Cu/TiN composite film,Ion implantation,Biological properties,Antibacterial properties