The high surface roughness of selective laser melting GH4169 alloy is a challenge that need to be resolved in its application. To replace the traditional acid based electrolyte

choline chloride-ethylene glycol system (Deep eutectic solvent

DES) was used for electrochemical polish GH4169 alloy fabricated by selective laser melting. In order to explore the ethanol addition effect on the electrochemical polishing behavior of the alloy

surface morphology

roughness

glossiness

wetting angle and electrochemical properties before and after electrochemical polishing have been investigated. The result indicates t

hat the surface quality of the specimens after electrochemical polishing has been significantly improved. Among them

when the molar ratio of choline chloride∶ethylene glycol∶ethanol is of 1∶1.9∶0.1

and the processing parameters are of temperature 60 ℃

time 30 min

voltage 3 V

magneton rotation speed 240 r/min and electrode spacing 13 mm

the surface of the specimen shows much more smooth and bright

and the roughness R

a

is (0.403 ± 0.010) μm

and the glossiness is (357.9 ± 2.2) GU. The wetting angle and electrochemical properties have also verified that the surface of the sample after electrochemical polishing is more beneficial to corrosion resistance. Meanwhile

the mechanism of the alloy electrochemical polishing in choline chloride-ethylene glycol system has also been discussed.