Selective Anodic Dissolution of Ag–Zn Alloys in the Eutectic Melt of Alkali Metal Chlorides at 300°С

N. P. Kulik N. P. Kulik , N. I. Shurov N. I. Shurov , N. K. Tkachev N. K. Tkachev
Российский электрохимический журнал
Abstract / Full Text

The peculiarities of electrochemical dealloying of two homogeneous Ag–Zn alloys in the (LiCl)0.57(CsCl)0.26(KCl)0.17 melt are studied. The zinc content in the alloys is 67 and 46 mol % which corresponds to the ε and β phases in the phase diagram at 300°С. Polarization curves are measured and the corrosion potential is determined to be –0.78 and –0.55 V, respectively, vs. Ag/AgCl reference electrode. The complete removal of zinc from the alloy surface is achieved by dealloying in the galvanostatic mode at the current density of about 20 mA/cm2 for the ε phase and 7 mA/cm2 for the β phase. On the surface of the Zn0.67Ag0.33 alloy, the characteristic homogeneous porous structures are formed in which the pores and the ligaments are approximately of the same size in the interval of 0.5–5 µm. For the Zn0.46Ag0.54 alloy, the dendrite structures with the silver particle size of about 0.5–4 and 5–20 µm are obtained.

Author information
  • Institute of High-Temperature Electrochemistry, Ural Branch, Russian Academy of Sciences, Yekaterinburg, Russia

    N. P. Kulik, N. I. Shurov & N. K. Tkachev

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