Nano Electrochemical Polishing of Titanium Alloy using Ionic Liquid

The titanium-aluminium-vanadium alloy (Ti-6Al-4V) is the most commonly used in bones, dental and articular prosthetics where high final surface quality is required. Electrochemical polishing is one of the method used to achieve a very low surface roughness. The classical electrochemical polishing process is done by using standard acidic solutions which associated with toxic and expensive disposal. The effect of voltage, rotation speed and polishing time on the surface roughness were investigated for electro-chemical mechanical polishing of Ti-6Al-4V using1-ethyl-3-methylimidazolium acetate. The experiment is conducted on a normal polishing machine which has been modified to suit the process. The ionic liquid acting as an electrolyte, so once the potential applied electrochemical dissolution and mechanical polishing occur at the same time. Then surface morphology is measured using AFM and SEM. The results shows that the surface roughness indexes gradually decreases with time of the process and it’s recommended to be in the range of 6-7 minutes. In addition, high voltages are not recommended for the process. Based on SEM and AFM analysis high rotation speed (150-200 rpm) and average voltages (35- 45 V) are the best input parameters for the process which result smooth surface with uniform scale formation.