Tribological and electrochemical properties of TiO2 films produced on Cp-Ti by sol-gel and SILAR in bio-simulated environment

Commercially pure titanium (Cp-Ti) is commonly used in different applications due to its good structural properties but its low mechanical and tribological properties restrict its usage areas. Therefore, different surface modifications based on TiO2 formation on material surfaces are applied to enhance surface features of materials. In this study, TiO2 films were produced on Cp-Ti by sol-gel and successive ionic layer adsorption and reaction (SILAR) methods to compare the effectiveness of these methods. The structural, morphological and mechanical features of TiO2 films were investigated by XRD, SEM and nano-indentation tester. The tribological features of coatings were characterized by using a pin-on-disk tribotester. The electrochemical behavior of TiO2 coatings was determined by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) analyses. The structural and mechanical analyses showed that sol-gel method caused the formation of more stable and hard film structures with good adhesion in comparison to SILAR method. For that reason, TiO2 films produced by sol–gel process exhibited better wear and corrosion resistance than the films produced by SILAR. © 2018 Elsevier B.V.