Electrodeposition of Zn-Mg Alloy in Ethylene Glycol-ZnCl2-MgCl2 Non-Aqueous Solution

Abstract

The electrodeposition of Zn–Mg alloy was investigated in a non-aqueous solution using ethylene glycol (EG) as solvent at 393 K. ZnCl2 and MgCl2 were used as Zn and Mg ion sources and could be dissolved in EG. Zn electrodeposits containing a certain amount of Mg were obtained in EG–ZnCl2–MgCl2 baths. 8.8 mol% of Mg was coelectrodeposited with Zn in the EG–ZnCl2–MgCl2 (85.0–7.5–7.5 mol%) bath at the cathodic current density of 300 Am–2, and Mg in this specimen was electrodeposited as Zn–Mg intermetallic compound of Mg2Zn11. The red rust occurrence time of Zn–8.8 mol%Mg alloy plated steel in 5 mass% NaCl aqueous solution at 308 K was about 16.0 times longer than that of Zn plated steel.