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2017228 
Journal Article 
Environmentally-friendly method for electroless Ni-P plating on magnesium alloy 
Seifzadeh, D; Rajabalizadeh, Z 
2013 
1 
Surface and Coatings Technology
ISSN: 0257-8972 
218 
119-126 
WOS:000316422900017 
In this paper, an environmentally-friendly procedure has been introduced for electroless nickel plating on AZ61 magnesium alloy. Magnesium alloy was firstly etched in nitric acid and then treated in a Cerium-lanthanum-permanganate (CLP) conversion coating bath. Finally, the electroless Ni-P deposition was carried out on the conversion coating from a sulfate solution. The microstructure of the CLP conversion coating was observed using Scanning Electron Microscopy (SEM), while the composition was analyzed by Energy Dispersive X-Ray Spectroscopy (EDX). Subsequently, deposited Ni-P coating was also characterized by its chemical composition, crystalline structure, morphology, and corrosion resistance. A uniform and amorphous nickel coating with high phosphorus content was successfully deposited on the pre-applied chemical conversion coating on the AZ61 alloy. An obvious passivation occurred for the nickel coating during the anodic polarization in 3.5 wt.% NaCl solution. Compared with the bare and CLP treated substrates, the Ni-P deposits showed more nobler corrosion potential and also lower corrosion current density. Open circuit potential (OCP) measurements and electrochemical impedance spectroscopy (EIS) experiments were carried out in 3.5 wt.% NaCl to determine the real anticorrosion performance of the Ni-P deposits. (C) 2013 Elsevier B.V. All rights reserved. 
Magnesium alloy; Electroless plating; Corrosion; Electrochemical impedance spectroscopy; SEM; X-ray diffraction