Nitinol (nickel titanium alloy) is well-known as one of the best biocompatible alloys because of itsexcellent performance. One of the main factors affecting the performance of nitinol cardiovascular stentis their unique surface properties. To improve the surface integrity of these stents, this paper presentedan electrolytic polishing method that added ethanol of different concentrations into a glycol - sodiumchloride electrolyte to find the optimal electrolyte composition. This paper also investigated the changein surface chemical composition. By plotting the voltage-current density curve and the time-currentdensity curve at various anhydrous ethanol concentrations, the optimal polishing voltage and anhydrousethanol concentration were determined to be 16 volts and 30%, respectively. According to the timecurrent density curve, the optimal polishing time was determined to be 20 min, when obtaining theminimum surface roughness (Ra1.837 nm). Furthermore, the surface composition and formationmechanism of the stent after electrolytic polishing were analysed by XPS.
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