中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 30 No. 2 February 2020 |
(1. Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran;
2. Dipartimento di Chimica, Materiali e Ingegneria Chimica Giulio Natta, Politecnico di Milano, Via Mancinelli 7, 20131, Milano, Italy)
Abstract:The potentiostatic electrodeposition of Zn-Ni-Mn was carried out in an alkaline solution with the addition of Mn salt. The effects of electrolyte Mn2+ concentration and deposition potential on the surface morphology, phase structure and corrosion behavior of coatings were studied. The results of corrosion polarization showed that the presence of higher Mn content in Zn-Ni-Mn coatings could lead to the formation of a good passive layer with a 7-fold increase in Rp of coating and a significant decrease in the corrosion current density compared to those of Zn-Ni coating. The XRD and the XPS analyses from the surface of Zn-Ni-Mn after corrosion test showed that the passive layer was composed of zinc hydroxide chloride, zinc oxide, zinc hydroxide carbonate, and manganese oxides.
Key words: Zn-Ni-Mn; electrodeposition; alkaline bath; phase structure; corrosion resistance; chemical composition