Artigo
Effect of citrate ions on the electrochemical behaviour of low-carbon steel in borate buffer solutions
Fecha
2004-03-01Registro en:
Corrosion Science. Oxford: Pergamon-Elsevier B.V., v. 46, n. 3, p. 529-545, 2004.
0010-938X
10.1016/S0010-938X(03)00170-7
WOS:000187856800003
2797127887030838
Autor
Universidade Estadual Paulista (Unesp)
Resumen
The electrochemical behaviour of cold-rolled low carbon steel was studied on both active and passive potential regions in borate buffer solutions with and without the addition of sodium citrate (NaCit). In the active region anodic charges increased significantly and RCT values decreased with citrate, due to the formation of soluble complexes. In the passive potential region the film formed at +0.4 V in borate buffer solution with and without 0.010 M NaCit is probably enriched by Fe3O4 oxide, while films formed at +0.8 V are probably enriched by gamma-Fe2O3. The equivalent circuit [R-s(R(CT)Q)] fitted all experimental impedance data. (C) 2003 Elsevier Ltd. All rights reserved.