Dependence on Surface Roughness of Electrical and Electrochemical Properties of Non-Porous and Porous Titanium Sheets

Titanium sheets are used in various electrochemical applications because of their excellent corrosion resistance and electrical stability.In this study, the effects of changes in surface roughness on sheet resistance and corrosion behavior of non-porous and porous titanium sheets were compared.In the as-received condition, the surface roughness (R a ) values of the non-porous and porous sheets were 0.06 and 2.41 µm, respectively, and the corresponding sheet resistance values were 4.82 and 10.62 mΩ/□.Potentiodynamic polarization tests performed in 0.5 M H 2 SO 4 showed that the corrosion potentials (E corr ) of the non-porous and porous sheets were -0.301 and -0.362 V, respectively, while the corrosion current densities (I corr ) were 0.117 and 0.812 µA･cm -2 , respectively.The porous sheet showed a higher I corr than the non-porous sheet, indicating relatively lower corrosion resistance.As surface roughness was increased by polishing with SiC sandpapers (G100-G1200), the sheet resistance increased in both sheets.In addition, the corrosion current density increased.EIS analysis also showed a decreasing tendency in polarization resistance (R p ).