Corrosion behavior of pure zinc and its alloy under thin electrolyte layer

doi:10.11890/1006-7191-106-416

Abstract

Abstract: The corrosion behavior of zinc and its alloy under thin electrolyte layers (TEL) in 0.1M NaCl solution was investigated by cathodic polarization curves and EIS. There was only one phase in pure zinc while zinc alloy consisted of eutectic phase and primary phase. Corrosion rate of zinc alloy was faster than that of pure zinc due to the effect of the micro-galvanic couples between the primary phase and the eutectic phase. The results indicated that corrosion rate of zinc alloy was greatly enhanced under TEL than that in bulk solution. Pure zinc exhibited minimum corrosion resistance as TEL decreased to 198 μm. Zinc and its alloy exhibited localized corrosion under TEL while it was more uniform in bulk solution. There were two capacitive loops in high frequency (HF) and middle frequency (MF) respectively, with finite length diffusion in low frequency (LF) presented in EIS. For pure zinc under TEL below 300 μm an additional inductive loop presented in MF-LF. The corrosion products and morphology were respectively examined by X-ray diffraction (XRD), FTIR (Fourier Transform Infra Red) and SEM-EDS. FTIR micro spectroscopy results indicated that the component of the corrosion products was similar at different section of the specimen surface but different in content.

Key words: Thin electrolyte layers, EIS, Cathodic polarization, FTIR micro spectroscopy, SEM

CLC Number:

O646.6

Liyun ZHENG, Fahe CAO, Wenjuan LIU,Bingli JIA, Jianqing ZHANG. Corrosion behavior of pure zinc and its alloy under thin electrolyte layer[J]. Acta Metallurgica Sinica (English Letters), 2010, 23(6): 416-430.

References

[1] S.Q. Sun, Q.F. Zheng, D.F. Li and J.G. Wen, Long-term atmospheric corrosion behaviour of aluminium alloys 2024 and 7075 in urban, coastal and industrial environments, Corros. Sci. 51 (2009) 719-727.

[2] D. de la Fuente, J.G. Castano and M. Morcillo, Long-term atmospheric corrosion of zinc, Corros. Sci. 49 (2007) 1420-1436.

[3] J. Morales, F. Diaz, J. Hernandez-Borges and S. Gonzalez, Atmospheric corrosion in subtropical areas: XRD and electrochemical study of zinc atmospheric corrosion products in the province of Santa Cruz de Tenerife (Canary Islands, Spain), Corros. Sci. 48 (2006) 361-371.

[4] R. Lindstrom, J.E. Svensson and L.G. Johansson, The atmospheric corrosion of zinc in the presence of NaCl the influence of carbon dioxide and temperature, J. Electrochem. Soc. 147 (2000) 1751-1757.

[5] G.A. El-Mahdy, A. Nishikata and T. Tsuru, AC impedance study on corrosion of 55%Al-Zn alloy-coated steel under thin electrolyte layers, Corros. Sci. 42 (2000) 1509-1521.

[6] S.C. Chung, A.S. Lin, J.R. Chang and H.C. Shih, EXAFS study of atmospheric corrosion products on zinc at the initial stage, Corros. Sci. 42 (2000) 1599-1610.

[7] B. Zhang, H.B. Zhou, E.H. Han and W. Ke, Effects of a small addition of Mn on the corrosion behaviour of Zn in a mixed solution, Electrochim. Acta 54 (2009) 6598-6608.

[8] G.A. El-Mahdy, Advanced laboratory study on the atmospheric corrosion of zinc under thin electrolyte layers, Corrosion 59 (2003) 505-510.

[9] Q. Qu, C.W. Yan, Y. Wan and C.N. Cao, Effects of NaCl and SO2 on the initial atmospheric corrosion of zinc, Corros. Sci. 44 (2002) 2789-2803.

[10] Q. Qu, L. Li, W. Bai and C.W. Yan, Initial atmospheric corrosion of zinc in presence of Na2SO4 and (NH4)2SO4, Transactions of Nonferrous Metals Society of China 16 (2006) 887-891.

[11] A. Nishikata, Y. Ichihara and T. Tsuru, An application of electrochemical impedance spectroscopy to atmospheric corrosion study, Corros. Sci. 37 (1995) 897-911.

[12] A. Nishikata, Y. Ichihara and T. Tsuru, Electrochemical impedance spectroscopy of metals covered with a thin electrolyte layer, Electrochim. Acta 41 (1996) 1057-1062.

[13] Y.L. Cheng, Z. Zhang, F.H. Cao, J.F. Li, J.Q. Zhang, J.M. Wang and C.N. Cao, A study of the corrosion of aluminum alloy 2024-T3 under thin electrolyte layers, Corros. Sci. 46 (2004) 1649-1667.

[14] N.D. Tomashov, Development of Electrochemical Theory of Metallic Corrosion, Corrosion 20 (1964) 7-14.

[15] S. Xing, Y. Li, J. Wu and Y. Yan, Electrochemical methods study on corrosion of 5% Al-Zn alloy-coated steel under thin electrolyte layers, Materials and Corrosion 9999 (2009) NA.

[16] B.G. An, X.Y. Zhang, E.H. Han and H.X. Li, Corrosion of zinc in simulated acid rain solution and under thin electrolyte layer formed by simulated acid rain solution, Acta Metall Sin 40 (2004) 202-206.

[17] I.L. Rozenfeld, Atmospheric corrosion of Metals, National Association of Corrosion Engineers, Houston (1972).

[18] Y.Y. Chen, S.C. Chung and H.C. Shih, Studies on the initial stages of zinc atmospheric corrosion in the presence of chloride, Corros. Sci. 48 (2006) 3547-3564.

[19] F.H. Assaf, S.S. Abd El-Rehiem and A.M. Zaky, Pitting corrosion of zinc in neutral halide solutions, Materials Chemistry and Physics 58 (1999) 58-63.

[20] F. Rosalbino, E. Angelini, D. Macciò, A. Saccone and S. Delfino, Influence of rare earths addition on the corrosion behaviour of Zn-5%Al (Galfan) alloy in neutral aerated sodium sulphate solution, Electrochim. Acta 52 (2007) 7107-7114.

[21] F. Rosalbino, E. Angelini, D. Macciò, A. Saccone and S. Delfino, Application of EIS to assess the effect of rare earths small addition on the corrosion behaviour of Zn-5% Al (Galfan) alloy in neutral aerated sodium chloride solution, Electrochim. Acta 54 (2009) 1204-1209.

[22] T. Zhang, C. Chen, Y. Shao, G. Meng, F. Wang, X. Li and C. Dong, Corrosion of pure magnesium under thin electrolyte layers, Electrochim Acta 53 (2008) 7921-7931.

[23] W. Liu, F. Cao, A. Chen, L. Chang, J. Zhang and C. Cao, Corrosion behaviour of AM60 magnesium alloys containing Ce or La under thin electrolyte layers. Part 1: Microstructural characterization and electrochemical behaviour, Corros. Sci. 52 (2010) 627-638.

[24] N.C. Barnard and S.G.R. Brown, Modelling the relationship between microstructure of Galfan-type coated steel and cut-edge corrosion resistance incorporating diffusion of multiple species, Corros. Sci. 50 (2008) 2846-2857.

[25] Y. Hamlaoui, F. Pedraza and L. Tifouti, Corrosion monitoring of galvanised coatings through electrochemical impedance spectroscopy, Corros. Sci. 50 (2008) 1558-1566.

[26] T.H. Muster and I.S. Cole, The protective nature of passivation films on zinc: surface charge, Corros. Sci. 46 (2004) 2319-2335.

[27] A.P. Yadav, A. Nishikata and T. Tsuru, Oxygen reduction mechanism on corroded zinc, J Electroanal Chem 585 (2005) 142-149.

[28] H. Zhang, X.G. Li, C.W. Du and H.B. Qi, Corrosion behavior and mechanism of the automotive hot-dip galvanized steel with alkaline mud adhesion, International Journal of Minerals, Metallurgy and Materials 16 (2009) 414-421.

[29] L. Sziráki, E. Szocs, Z. Pilbáth, K. Papp and E. Kálmán, Study of the initial stage of white rust formation on zinc single crystal by EIS, STM/AFM and SEM/EDS techniques, Electrochim. Acta 46 (2001) 3743-3754.

[30] C. Cachet, F. Ganne, G. Maurin, J. Petitjean, V. Vivier and R. Wiart, EIS investigation of zinc dissolution in aerated sulfate medium. Part I: bulk zinc, Electrochim. Acta 47 (2001) 509-518.

[31] M.C. Li, M. Royer, D. Stien, A. Lecante and C. Roos, Inhibitive effect of sodium eperuate on zinc corrosion in alkaline solutions, Corros. Sci. 50 (2008) 1975-1981.

[32] A.P. Yadav, A. Nishikata and T. Tsuru, Evaluation of impedance spectra of zinc and galvanised steel corroding under atmospheric environments, Corros Eng Sci Techn 43 (2008) 23-29.

[33] J.R. Vilche, F.E. Varela, G. Acuna, E.N. Codaro, B.M. Rosales, A. Fernandez and G. Moriena, A Survey of Argentinean Atmospheric Corrosion .1. Aluminum and Zinc Samples, Corros. Sci. 37 (1995) 941-961.

[34] Z.I. Ortiz, P. Diaz-Arista, Y. Meas, R. Ortega-Borges and G. Trejo, Characterization of the corrosion products of electrodeposited Zn, Zn-Co and Zn-Mn alloys coatings, Corros. Sci. 51 (2009) 2703-2715.

[35] M.C. Bernard, A. Hugotlegoff, D. Massinon and N. Phillips, Underpaint Corrosion of Zinc-Coated Steel Sheet Studied by in-Situ Raman-Spectroscopy, Corros. Sci. 35 (1993) 1339-1349.

[36] Q. Qu, C. Yan, Y. Wan and C. Cao, Effects of NaCl and SO2 on the initial atmospheric corrosion of zinc, Corros. Sci. 44 (2002) 2789-2803.

[37] I. Suzuki, The behavior of corrosion products on zinc in sodium chloride solution, Corros. Sci. 25 (1985) 1029-1034.

[38] Z.Y. Chen, D. Persson and C. Leygraf, Initial NaCl-particle induced atmospheric corrosion of zinc-effect of CO2 and SO2, Corros. Sci. 50 (2008) 111-123.

[39] I.S. Cole, W.D. Ganther, S.A. Furman, T.H. Muster and A.K. Neufeld, Pitting of zinc: Observations on atmospheric corrosion in tropical countries, Corros. Sci. 52 (2010) 848-858.