Electropolishing of WCu composite in a deep eutectic solvent

The possibility of using a deep eutectic mixture of choline chloride and ethylene glycol in a 1:2 molar ratio (ethaline) for the electropolishing of a WCu composite (similar to 71 wt.% of W and similar to 12 wt.% of Cu) has been shown for the first time. It was demonstrated that 20 min electropolishing in ethaline at a temperature of 25 degrees C causes significant leveling of the surfaces and decreases the amount of defects and the depth of scratches. It was also found that electropolishing of WCu composite in ethaline was accompanied by changes in the elemental surface composition: a decrease in Cu, C and O concentrations and an increase in W concentration were observed. It was shown that such changes in the surface elemental composition of WCu samples, together with the leveling of the surfaces and elimination of defects, led to almost a fourfold improvement in the corrosion resistance of the samples in 10 wt.% aqueous NaCl solution.

Automated summary

The study demonstrates for the first time the possibility of using a deep eutectic mixture of choline chloride and ethylene glycol for electropolishing of WCu composite, leading to significant improvement in surface leveling and corrosion resistance of the material.