Published June 15, 2007 | Version v1
Journal article

A study of direct- and pulse-current chromium electroplating on rotating cylinder electrode (RCE)

  • 1. Department of Mechanical Engineering, Chang Gung University, Taoyuan 333, Taiwan (China)
  • 2. Department of Materials Engineering, Ming Chi University of Technology, Taipei 243, Taiwan (China)

Description

Direct- and pulse-current (DC and PC) chromium electroplating on Cr-Mo steel were performed in a sulfate-catalyzed chromic acid solution at 50 deg. C using a rotating cylinder electrode (RCE). The electroplating cathodic current densities were at 30, 40, 50 and 60 A dm-2, respectively. The relationship between electroplating current efficiency and the rotating speed of the RCE was studied. The cross-sectional microstructure of Cr-deposit was examined by transmission electron microscope (TEM). Results showed that DC-plating exhibited higher current efficiency than the PC-plating under the same conditions of electroplating current density and the rotating speed. We found the critical rotating speed of RCE used in the chromium electroplating, above this rotating speed the chromium deposition is prohibited. At the same plating current density, the critical rotating speed for DC-plating was higher than that for PC-plating. The higher plating current density is, the larger difference in critical rotating speeds appears between DC- and PC-electroplating. Equiaxed grains, in a nanoscale size with lower dislocation density, nucleate on the cathodic surface in both DC- and PC-electroplating. Adjacent to the equiaxed grains, textured grains were found in other portion of chromium deposit. Fine columnar grains were observed in the DC-electroplated deposit. On the other hand, very long slender grains with high degree of preferred orientation were detected in PC-electroplated deposit

Additional details

Identifiers

DOI
10.1016/j.apsusc.2007.01.124;
PII
S0169-4332(07)00207-3;

Publishing Information

Journal Title
Applied Surface Science
Journal Volume
253
Journal Issue
16
Journal Page Range
p. 6829-6834
ISSN
0169-4332
CODEN
ASUSEE

Conference

Title
4. international workshop on basic aspects of nonequilibrium plasmas interacting with surfaces - Negative ions, their function and designability; 4. EU-Japan joint symposium on plasma processes
Dates
30 Jan - 1 Feb 2006
Place
Lake Kawaguchi (Japan)

Optional Information

Copyright
Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.