A Study on the Effect of Si Content on Corrosion-Wear Behaviors of Diamond-Like Carbon Films in the Simulated Body Fluid Environment

摘要

In a method to improve resistance to wear, corrosion and mechanical properties of protective coating, DLC coatings have been extensively studied over the past several years due to their unique combination of properties. Especially, Si-DLC coatings have been attracting increasing interest of researchers since they have a great potential for solving some of the major disadvantages of pure DLC coatings. Si-incorporated diamond-like carbon (Si-DLC) coatings ranging from 0 to 2 at. percent were deposited on Ti alloy substrate by means of r.f. plasma-assisted chemical vapor deposition (r.f. PACVD) technique, using mixtures of benzene (C_6H_6) and silane (SiEL_4) as the reaction gases. Corrosion and wear behavior of DLC coatings was investigated by electrochemical techniques (potentiodynamic polarization test and electrochemical impedance spectroscopy), tribological techchnique(wear test) and surface analyses (atomic force microscopy, scanning electron microscopy and Raman spectroscopy). It was found that DLC coatings with increasing Si content could acquire improved corrosion and wear resistance in the simulated body fluid environment (0.89 wt. percent NaCl of pH 7.4 at 37 deg C).