Biotribological properties of Ti-6Al-4V alloy treated with self-assembly multi-walled carbon nanotube coating

Ti-6Al-4V alloy has been widely applied in biomedical field due to its good biocompatibility, non-toxicity and excellent anti-corrosion. However, the poor tribological performance limits its application. In this paper, in order to enhance the biotribological properties of Ti-6Al-4V alloy, carboxylic multi-walled carbon nanotubes (CMWNT) coatings were grafted on the surface by chemical self-assembly technology. Raman spectroscopy and scanning electron microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDX) were utilized to characterize the microstructures of the coatings. The CMWNT coatings showed lower coefficient of friction and wear rates wider dry sliding and simulated body fluid (SBF) lubrication. Furthermore, the biotribological mechanisms of CMWNT coatings under both conditions were discussed. Analyses of worn surfaces indicated that the rolling friction between the microtubes due to the spalling and fracture of CMWNT during the friction process was a major factor for improving biotribological behavior.