Microstructure And Biocompatibility Of Fluorine And Nitrogen Doped DLC Films On TiNi Alloys

Fluorine and Nitrogen doped Diamond-like carbon films were deposited successfully on the TiNi alloys by plasma immersion ion implantation and deposition (PIIID). It should be noted that the Fluorine doped films (F-DLC) were used by CF4 and graphite and Nitrogen doped films (N-DLC) were used N2 and graphite. The surface characteristics, microstructure, mechanical properties, electrochemical corrosion behavior and hemocompatibility of TiNi alloys coated with doping DLC films have been systematically investigated by XPS, Raman spectroscopy, IR, AFM, nanoindentation tests, nanoscratch tests, big-load-scratch test, electrochemical measurement and hemocompatibility experiments.The results show that F and N were successfully doped in DLC films and doping has obvious influence on the surface characteristics and structures of DLC films. With the increase of the CF4 flux,the sp3/sp2 ratio and RMS values of F-DLC films are decreased. With the increase of the N2 flux,the sp3/sp2 ratio of F-DLC films are decreased and RMS values increased.With increasing the CF4 and N2 flux, the nano-hardness and elastic modulus of DLC films decrease. With increasing the CF4 flux, adhesion strength decrease and with increasing the N2 flux, adhesion strength increases first and then decreases.With increasing the CF4 flux, the corrosion resistance of F-DLC films increases first and then decreases. With increasing the N2 flux, the corrosion resistance of N-DLC films increases first and then decreases.With increasing the CF4 flux, contect angles of F-DLC films increased and with increasing the N2 flux, ontect angles of F-DLC films decreased.The hemocompatibility of DLC are improved by F doped. With increasing the CF4 flux, the adhered amount of platelet and activation ratio of F-DLC films decrease. With increasing the N2 flux, the adhered amount of platelet and activation ratio of F-DLC films increase.