Effect of Incorporating Carbon Nanotubes into Electrolyte on Surface Morphology of Micro Arc Oxidized Cp-Ti

(Doç. Dr. Murat Baydoğan, Araş. Gör. Faiz Muhaffel, Selim Kaan Yazıcı)


In the present study, the effects of carbon nanotubes incorporation into oxide coatings on surface morphology were investigated. The oxide coatings formed on commercially pure titanium (Cp-Ti) by micro arc oxidation (MAO) process with respect to varying carbon nanotubes concentration in alkaline electrolyte and applied voltage. Results showed that carbon nanotubes were successfully deposited on the coating surface and especially within the pores generated by discharge channels during MAO process as confirmed by SEM examinations. Meanwhile, the applied voltage and the concentration of the carbon nanotubes in the electrolyte were increased, the size of pores on the coating surface also increased. On the contrary, the number of pores on the coating surface clearly decreased. Additionally, higher concentration of carbon nanotubes in the electrolyte resulted in a decrement in the coating thickness and stimulated aluminum titanate (Al2TiO5) formation in the oxide coating.        

Fig. Raman spectra of MAO, CNTs-2 and CNTs-4 samples oxidized at the positive voltage of 300 V.