Electrodeposition of Cobalt Rich Zn-Co alloy Coatings from Citrate Bath

Materials Research

Julyana Ribeiro Garcia¹  Dalva Cristina Baptista Do Lago¹  Lilian Ferreira De Senna¹ 

[1] ,Rio de Janeiro State University Chemistry Institute Corrosion and Electrochemistry LaboratoryRio de Janeiro RJ ,Brazil

关键词: Electrodeposition;    Zn-Co alloy coatings;    sodium citrate;    corrosion protection;   

DOI  :  10.1590/S1516-14392014005000096

来源: SciELO

【 摘 要 】

Zn-Co alloy coatings were produced on carbon steel, at room temperature, from citrate baths (0.100 mol L-1) containing [Zn2+]= [Co2+] = 0.05 mol L-1. Coatings with %m/m Co > %m/m Zn were observed under all deposition conditions, except for I = 10 A m-2. As the current density (I) was increased, a significant decrease (p<0.05) in %m/m Zn was noted, and the highest value of % m/m Co was observed at 80 A m-2. The Co-rich coatings presented refined microstructure, with small grain sizes. The smallest Icorr of the studied substrate/coatings systems, 2.4 µA cm-2, was obtained at I = 10 A m-2. Under these conditions, the coatings contained ~ 30 % m/m Co and 70 % m/m Zn and only the γ-ZnCo phase was obtained. The Icorr found in the present work is smaller than those usually found in the literature for Zn-Co coatings with small Co content.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License