Enhancement of the surface characteristics of Ti-based biomedical alloy by electropolishing in environmentally friendly deep eutectic solvent (Ethaline)

Abstract

This paper reports the results of the study on electrochemical polishing of Ti-based alloy using an ecologically friendly deep eutectic solvent, Ethaline. The electropolishing treatment was performed in a potentiostatic mode (E=+3.0 V and E=+4.0 V) at the temperature of 25 °C for 30–40 min. It was shown that the electropolishing in Ethaline ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The atomic-force microscopy revealed that the electrochemical polishing of titanium alloy in Ethaline yielded formation of specific surface patterns with nanoscale irregularities in the form of prolonged hemispheres. The correlations between surface roughness coefficients and wettability parameters were established and discussed. The electrochemical processes occurring during electrochemical polishing of Ti-based alloy in Ethaline were examined. The adjustment of processing time and electrode potential of electropolishing allows controllably and flexibly tuning the surface roughness and wettability of titanium-containing alloy. It issuggested that the electropolishing of the surfaces of Ti-based alloys in deep eutectic solvent can be successfully used for the processing of different biomedical products.