ELECTROCHEMICAL BEHAVIOR OF (001), (100) AND (110) Ti SINGLE CRYSTALS UNDER SIMULATED BODY FLUID CONDITION

摘要

In this paper, the electrochemical behavior of Ti single crystals and CP Ti under simulated body fluid condition was investigated. (001), (100) and (110) single crystals were used for this investigation. Electrochemical Impedance Spectroscopy (EIS) was used to characterize the electrochemical behavior of the interface between the substrates and the electrolyte. Potentiodynamic polarization was also performed to characterize the corrosion resistance of the different Ti surfaces. The EIS spectra were presented in Bode plot and interpreted in terms of appropriate electrical circuits. It was found that the resistance to charge transfer, Rct, of the (001) single crystal was 5.1 MΩ cm~2 compared to 3.1 MΩ cm~2 and 3.3 MΩ cm~2 for the (100) and (110) single crystals respectively. The R_(ct) of Cp Ti was 1.1 MΩ cm~2. It should be mentioned that the resistance to charge transfer is inversely proportional to the corrosion rate. The Potentiodynamic polarization curve have also shown that the corrosion rate and passive current of (001) single crystal were lower than those of (100) and (110) single crystals. These results have shown that the (001) basal plane which is the most densely packed plane had higher corrosion resistance compared to (100) and (110) planes which have lower planar atomic densities. Also, The Cp Ti was found to have the least corrosion resistance, most probably due to the presence of grain boundaries which are areas of disorder in the material.