Corrosion behaviour of weathering steel in diluted Qinghai salt lake water in a laboratory accelerated test that involved cyclic wet/dry conditions

The corrosion behaviour of CortenA weathering steel has been investigated using a laboratory accelerated test that involved cyclic wet/dry conditions in Qinghai salt lake water diluted 30 times The characteristics of the rust layers on tested samples were observed by SEM and EPMA analyzed by IRS and XRD and studied by polarization and EIS measurements The weight loss was almost linear indicating that the rust layer had no retarding effect on the corrosion process The crystalline components of the rust layers consisted primarily of beta-FeOOH magnetite (Fe(3)O(4)) and gamma-FeOOH As the corrosion proceeded the amount of beta-FeOOH decreased while that of magnetite and gamma-FeOOH increased XRD EDAX and EPMA indicated that the complex corrosion products magnesioferrite (MgFe(2)O(4)) and iowaite (Mg(4)Fe(OH)(8)OCl 4H(2)O) probably existed in the rust layer in which case they will have had an important Influence on the protectiveness of the rust layer The results of electrochemical measurements showed that the rust layer exhibited high reduction reactivity which facilitated the corrosion of weathering steel in the wetting process The large rust capacitance and small rust resistance indicated that the rust layer had a loose and porous structure which provided poor protection (c) 2010 Elsevier B V All rights reserved

[1]  Y. Hisamatsu,et al.  Nature of Atmospheric Rust on Iron , 1980 .

[2]  P. Dillmann,et al.  Advances in understanding atmospheric corrosion of iron. II. Mechanistic modelling of wet–dry cycles , 2004 .

[3]  E. Han,et al.  Characterization of the rust formed on weathering steel exposed to Qinghai salt lake atmosphere , 2008 .

[4]  R. D. Armstrong,et al.  The effect of roughness on the impedance of the interface between a solid electrolyte and a blocking electrode , 1976 .

[5]  H. Saricimen,et al.  Initial stages of atmospheric corrosion of steel in the Arabian Gulf , 1991 .

[6]  T. Misawa,et al.  The thermodynamic consideration for Fe-H2O system at 25°C‡ , 1973 .

[7]  Martin Stratmann,et al.  The mechanism of the oxygen reduction on rust-covered metal substrates , 1994 .

[8]  T. Misawa,et al.  The mechanism of formation of iron oxide and oxyhydroxides in aqueous solutions at room temperature , 1974 .

[9]  T. Pajkossy,et al.  Electrochemistry at fractal interfaces: the coupling of ac and dc behaviour at irregular electrodes , 1990 .

[10]  Yuantai Ma,et al.  The effect of β-FeOOH on the corrosion behavior of low carbon steel exposed in tropic marine environment , 2008 .

[11]  Masato Yamashita,et al.  Composition and protective ability of rust layer formed on weathering steel exposed to various environments , 2006 .

[12]  J. Marco,et al.  Characterization of the corrosion products formed on carbon steel after exposure to the open atmosphere in the Antarctic and Easter Island , 2000 .

[13]  Eva Johansson,et al.  Corrosion Study of Carbon Steel and Zinc-Comparison Between Field Exposure and Accelerated Tests , 1995 .

[14]  F. Corvo,et al.  Outdoor and indoor atmospheric corrosion of carbon steel , 1999 .

[15]  H. Shih,et al.  The corrosion mechanisms of carbon steel and weathering steel in SO2 polluted atmospheres , 1997 .

[16]  B. Tribollet,et al.  Impedance spectroscopic study of a steel electrode in condition of scaling and corrosion: Interphase model , 1999 .

[17]  R. Nyquist,et al.  INFRARED SPECTRA OF INORGANIC COMPOUNDS , 1971 .

[18]  J. J. Wang,et al.  Corrosion behavior of weathering steel in marine atmosphere , 2003 .

[19]  A. Raman,et al.  The application of infrared spectroscopy to the study of atmospheric rust systems—I. Standard spectra and illustrative applications to identify rust phases in natural atmospheric corrosion products , 1991 .

[20]  Koji Hashimoto,et al.  The Mechanism of Atmospheric Rusting and the Protective Amorphous Rust on Low Alloy Steel(Chemistry) , 1974 .

[21]  M. Itagaki,et al.  Electrochemical impedance of thin rust film of low-alloy steels , 2004 .

[22]  T. Baird,et al.  Electron microscope studies of iron corrosion products in water at room temperature , 1982 .

[23]  J. Defourny,et al.  A literature survey on the development of an accelerated laboratory test method for atmospheric corrosion of precoated steel products , 1993 .

[24]  I. Matsushima,et al.  On the protective nature of atmosph rust on low-alloy steel , 1971 .

[25]  Blanca R. de Meybaum,et al.  Characterization of Atmospheric Corrosion Products on Weathering Steels , 1980 .

[26]  U. R. Evans.  Mechanism of rusting , 1969 .

[27]  Martin Stratmann,et al.  An electrochemical study of phase-transitions in rust layers , 1983 .

[28]  Kazuhiko Noda,et al.  Electrochemical Behavior of Rust Formed on Carbon Steel in a Wet/Dry Environment Containing Chloride Ions , 2000 .

[29]  Masato Yamashita,et al.  The long term growth of the protective rust layer formed on weathering steel by atmospheric corrosion during a quarter of a century , 1994 .

[30]  Atsushi Nishikata,et al.  Electrochemical impedance study on galvanized steel corrosion under cyclic wet–dry conditions––influence of time of wetness , 2004 .

[31]  K. Asami,et al.  In-depth distribution of rusts on a plain carbon steel and weathering steels exposed to coastal-industrial atmosphere for 17 years , 2003 .

[32]  Martin Stratmann,et al.  In situ Möβbauer spectroscopic study of reactions within rust layers , 1989 .

[33]  T. Misawa,et al.  The mechanism of atmospheric rusting and the effect of Cu and P on the rust formation of low alloy steels , 1971 .