Influence of zirconium doping on the growth of apatite and corrosion behavior of DLC-coated titanium alloy Ti-13Nb-13Zr

摘要

Ti-13Nb-13Zr was coated with diamond-like carbon (DLC) and zirconium-doped DLC by plasma-enhanced chemical vapor deposition and sputtering. The corrosion current of the substrate is not affected after coating, and corrosion potential shifts towards nobler values in Hanks' solution. Electrochemical impedance spectroscopy studies show that Zr-DLC samples behave like an ideal capacitor. Field emission scanning electron microscopy (FESEM) images after 7 days of immersion show absence of apatite on DLC-coated sample and its presence on Zr-doped DLC, but to a lesser extent as compared with that on the uncoated substrate. XPS and Energy-dispersive X-ray spectroscopy (EDS) of samples immersed in Hanks' solution show presence of calcium, phosphorous and oxygen in hydroxide/phosphate form on the substrate and Zr-DLC.