Title: Electrodeposition of zinc-nickel coating on AZ31 magnesium alloy
Authors: P. Zhu; L.Y. Wang; X.J. Zhang; M. Zhou
Addresses: College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China. ' College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China. ' College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China. ' Semiconductor Manufacturing International (Shanghai) Corporation, 18 Zhangjiang Road, Shanghai 201203, China
Abstract: Although magnesium and its alloys have excellent physical and mechanical properties, they are highly susceptible to corrosion to hinder their widespread use in many applications. In this paper, zinc-nickel coating is directly electrodeposited on AZ31 magnesium alloy using an aqueous solution containing zinc fluoride, basic nickel carbonate, and citrate. Various parameters such as pH value, additive, complexing agent, current density, and electrodepositing temperature are studied to understand electrodepositing zinc-nickel coating on AZ31 magnesium alloy. SEM observation shows that the morphology of zinc-nickel coating is typical dense nodular structure, and the coating compositions are found to be 86 wt% zincs and 14 wt% nickels. Adhesion strength result shows that there is not peeling for zinc-nickel coating with the grid of 1 × 1 cm treated by the adhesive tape. The immersion test in 5% NaCl solution reveals that the zinc-nickel coating has good dense property.
Keywords: magnesium alloys; electrodeposition; zinc nickel alloys; corrosion resistance.
DOI: 10.1504/IJSURFSE.2012.049922
International Journal of Surface Science and Engineering, 2012 Vol.6 No.4, pp.351 - 361
Received: 24 Aug 2011
Accepted: 21 Mar 2012
Published online: 21 Aug 2014 *