Table of Contents
ISRN Corrosion
Volume 2013 (2013), Article ID 921825, 6 pages
http://dx.doi.org/10.1155/2013/921825
Research Article

An Investigation on Dislocation Density in Cold-Rolled Copper Using Electrochemical Impedance Spectroscopy

1Technical Inspection Engineering Department, Petroleum University of Technology, Abadan, Iran
2Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111, Iran
3Department of Materials Science and Engineering, Shahid Chamran University of Ahvaz, Iran

Received 7 February 2013; Accepted 1 March 2013

Academic Editors: C.-H. Hsu and S. J. Lee

Copyright © 2013 Elyas Rafiee et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Variation of electrochemical impedance with dislocation density was investigated using electrochemical impedance spectroscopy (EIS). For this purpose, EIS measurements were carried out on 10, 20, 30, 40, and 50% cold-rolled commercially pure copper in 0.1 M NaCl (pH = 2) solution. Nyquist plots illustrated that the electrochemical reactions are controlled by both charge transfer and diffusion process. Increasing dislocation density, the magnitude of electrochemical impedance of samples was decreased. Decreasing magnitude of impedance at intermediate frequencies indicated increasing double-layer capacitance. Charge transfer resistance decreased from value 329.6 Ωcm2 for annealed sample to 186.3 Ωcm2 for sample with maximum dislocation density (). Phase angles were lower for samples that contained more dislocation density, indicating more tendencies to loss of electrons and releasing atoms into electrolyte.