文摘
To improve the corrosion resistance of biomedical nickel titanium (NiTi) alloy, a polymeric allylamine film is deposited by plasma polymerization. The chemical composition, surface morphology, and thickness of the polymer film are investigated with X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The corrosion behavior of the coated NiTi and bare NiTi samples is compared by polarization test and electrochemical impedance spectroscopy (EIS) in simulated body fluid. The results show that the polymeric film lowers the corrosion current density and increases the polarization resistance, indicating improved corrosion resistance. The plasma polymerized coating is expected to reduce corrosion risks of biomedical NiTi alloy in clinical use.