Effect of added ethanol in ethylene glycol-NaCl electrolyte on titanium electropolishing

This study examined the effects of adding ethanol, a typical polar solvent, to an ethylene glycol-NaCl electrolyte solution used for Ti electropolishing. The electropolishing range was determined by measuring current density-voltage curve as a function of the ethanol concentration. When 20 vol.% ethanol was added to the electrolyte solution, a mirror-like surface was obtained by adjusting the TiCl4 layer from the substrate. With the exception of oxygen-bonded species, only metallic Ti was detected on the electropolished surface with X-ray photoelectron spectroscopy. The minimum surface roughness, which was measured with atomic force spectroscopy, was 2.341 nm.