All Title Author
Keywords Abstract


Corrosion Behaviour of a New Low-Nickel Stainless Steel Reinforcement: A Study in Simulated Pore Solutions and in Fly Ash Mortars

DOI: 10.1155/2012/847323

Full-Text   Cite this paper   Add to My Lib

Abstract:

The present paper studies the corrosion behaviour of a new lower-cost type of austenitic stainless steel (SS) with a low nickel content in alkaline-saturated calcium hydroxide solution (a simulated concrete pore (SCP) solution) with sodium chloride (0.0%, 0.4%, 1.0%, 2.0%, 3.0%, and 5.0% NaCl) and embedded in alkali-activated fly ash (AAFA) mortars manufactured using two alkaline solutions, with and without chloride additions (2% and 5%), in an environment of constant 95% relative humidity. Measurements were performed at early age curing up to 180 days of experimentation. The evolution with time of electrochemical impedance spectroscopy was studied. values obtained in SCP solution or in fly ash mortars were so high that low-nickel SS preserved its passivity, exhibiting high corrosion resistance 1. Introduction Steel reinforcements embedded in concrete are protected from corrosion by a thin oxide film formed on their surfaces and maintained by the highly alkaline environment of the surrounding concrete, usually with a pH of 12-13 [1]. However, the presence of chlorides can lead to damaging effects on passivity and the appearance of pitting corrosion when chloride ions reach the metal/concrete interface. Chloride ions are commonly found in construction materials and may originate from the external environment, as in the case of marine environments, deicing salts and acid rain [2]. While thermodynamic can predict whether a corrosion reaction will take place, it does not provide an indication of the rate of corrosion reactions. The reaction kinetics depends on the determinant factors such as humidity, oxygen, and alkalinity medium. These factors can speed up the corrosion process [3, 4]. Together with cathodic protection and corrosion inhibitors, stainless steel (SS) reinforcements are a reliable way to guarantee the durability of reinforced concrete structures (RCSs) in extremely aggressive environments [5, 6]. Although SS reinforcements may be the most economical solution on the long term [7, 8], the initial cost involved has so far limited their use. For this reason, new SSs, in which the nickel content (subject to considerable price fluctuations due to stock market factors) is partly replaced by other elements [9, 10], are being evaluated as possible alternatives to traditional carbon steel [11, 12]. This new low-nickel SS could mean a saving of about 15–20% compared to conventional AISI 304 SS. Low-nickel austenitic SSs exhibit attractive properties that are comparable to those of traditional austenitic SSs, such as good corrosion resistance, high

References

[1]  L. Bertolini, B. Elsener, P. Pedeferri, and R. Polder, Corrosion of Steel in Concrete: Prevention, Diagnosis, Repair, Wiley VCH, New York, NY, USA, 2004.
[2]  M. A. G. Tommaselli, N. A. Mariano, and S. E. Kuri, “Effectiveness of corrosion inhibitors in saturated calcium hydroxide solutions acidified by acid rain components,” Construction and Building Materials, vol. 23, no. 1, pp. 328–333, 2009.
[3]  J. M. Miranda, A. Fernández-Jiménez, J. A. González, and A. Palomo, “Corrosion resistance in activated fly ash mortars,” Cement and Concrete Research, vol. 35, no. 6, pp. 1210–1217, 2005.
[4]  D. M. Bastidas, A. Fernández-Jiménez, A. Palomo, and J. A. González, “A study on the passive state stability of steel embedded in activated fly ash mortars,” Corrosion Science, vol. 50, no. 4, pp. 1058–1065, 2008.
[5]  R. Montoya, W. Aperador, and D. M. Bastidas, “Influence of conductivity on cathodic protection of reinforced alkali-activated slag mortar using the finite element method,” Corrosion Science, vol. 51, no. 12, pp. 2857–2862, 2009.
[6]  M. B. Valcarce and M. Vázquez, “Carbon steel passivity examined in alkaline solutions: the effect of chloride and nitrite ions,” Electrochimica Acta, vol. 53, no. 15, pp. 5007–5015, 2008.
[7]  N. R. Baddoo, “Stainless steel in construction: a review of research, applications, challenges and opportunities,” Journal of Constructional Steel Research, vol. 64, no. 11, pp. 1199–1206, 2008.
[8]  A. Bautista, G. Blanco, F. Velasco, and M. A. Martínez, “Corrosion performance of welded stainless steels reinforcements in simulated pore solutions,” Construction and Building Materials, vol. 21, no. 6, pp. 1267–1276, 2007.
[9]  R. Merello, F. J. Botana, J. Botella, M. V. Matres, and M. Marcos, “Influence of chemical composition on the pitting corrosion resistance of non-standard low-ni high-mn-n duplex stainless steels,” Corrosion Science, vol. 45, no. 5, pp. 909–921, 2003.
[10]  L. Freire, X. R. Nóvoa, G. Pena, and V. Vivier, “On the corrosion mechanism of aisi 204cu stainless steel in chlorinated alkaline media,” Corrosion Science, vol. 50, no. 11, pp. 3205–3212, 2008.
[11]  D. Trejo and P. J. Monteiro, “Corrosion performance of conventional (ASTM a615) and low-alloy (ASTM A706) reinforcing bars embedded in concrete and exposed to chloride environments,” Cement and Concrete Research, vol. 35, no. 3, pp. 562–571, 2005.
[12]  L. Veleva, M. A. Alpuche-Aviles, M. K. Graves-Brook, and D. O. Wipf, “Comparative cyclic voltammetry and surface analysis of passive films grown on stainless steel 316 in concrete pore model solutions,” Journal of Electroanalytical Chemistry, vol. 537, no. 1-2, pp. 85–93, 2002.
[13]  G. S. Frankel, “Pitting corrosion of metals: a review of the critical factors,” Journal of the Electrochemical Society, vol. 145, no. 6, pp. 2186–2198, 1998.
[14]  M. C. García-Alonso, M. L. Escudero, J. M. Miranda et al., “Corrosion behaviour of new stainless steels reinforcing bars embedded in concrete,” Cement and Concrete Research, vol. 37, no. 10, pp. 1463–1471, 2007.
[15]  M. C. García-Alonso, J. A. González, J. Miranda et al., “Corrosion behaviour of innovative stainless steels in mortar,” Cement and Concrete Research, vol. 37, no. 11, pp. 1562–1569, 2007.
[16]  A. Bautista, G. Blanco, and F. Velasco, “Corrosion behaviour of low-nickel austenitic stainless steels reinforcements: a comparative study in simulated pore solutions,” Cement and Concrete Research, vol. 36, no. 10, pp. 1922–1930, 2006.
[17]  J. A. Gonzalez, S. Feliu, P. Rodriguez, E. Ramirez, C. Alonso, and C. Andrade, “Some questions on the corrosion of steel in concrete. Part I: when, how and how much steel corrodes,” Materials and Structures, vol. 29, pp. 40–46, 2006.
[18]  T. Smith, “New electrochemical cell for pitting corrosion testing,” Corrosion Science, vol. 29, pp. 135–140, 1988.
[19]  “Stainless steel. Part 1: list of stainless steel,” UNE-EN 10088-1:2006.
[20]  “Standard specification for chromium and chromium-nickel stainless steel plate, sheet, and strip for pressure vessels and for general applications.,” ASTM A240/A240M-11b.
[21]  O. Poupard, A. A?t-Mokhtar, and P. Dumargue, “Impedance spectroscopy in reinforced concrete: procedure for monitoring steel corrosion: part I development of the experimental device,” Journal of Materials Science, vol. 38, no. 13, pp. 2845–2850, 2003.
[22]  V. Feliu, J. A. González, C. Andrade, and S. Feliu, “Equivalent circuit for modelling the steel-concrete interface. I. experimental evidence and theoretical predictions,” Corrosion Science, vol. 40, no. 6, pp. 975–993, 1998.
[23]  T. Hong, G. W. Walter, and M. Nagumo, “The observation of the early stages of pitting on passivated type 304 stainless steel in a 0.5?M NaCl solution at low potentials in the passive region by using the AC impedance method,” Corrosion Science, vol. 38, no. 9, pp. 1525–1533, 1996.
[24]  W. Chen, R.-G. Du, C.-Q. Ye, Y.-F. Zhu, and C.-J. Lin, “Study on the corrosion behavior of reinforcing steel in simulated concrete pore solutions using in situ Raman spectroscopy assisted by electrochemical techniques,” Electrochimica Acta, vol. 55, no. 20, pp. 5677–5682, 2010.
[25]  U. Rammelt and G. Reinhard, “On the applicability of a constant phase element (CPE) to the estimation of roughness of solid metal electrodes,” Electrochimica Acta, vol. 35, no. 6, pp. 1045–1049, 1990.
[26]  M. Leibig and T. C. Halsey, “The double layer impedance as a probe of surface roughness,” Electrochimica Acta, vol. 38, no. 14, pp. 1985–1988, 1993.
[27]  S. Fajardo, D. M. Bastidas, M. Criado, M. Romero, and J. M. Bastidas, “Corrosion behaviour of a new low-nickel stainless steel in saturated calcium hydroxide solution,” Construction and Building Materials, vol. 25, no. 11, pp. 4190–4196, 2011.
[28]  M. Criado, D. M. Bastidas, S. Fajardo, A. Fernández-Jiménez, and J. M. Bastidas, “Corrosion behaviour of a new low-nickel stainless steel embedded in activated fly ash mortars,” Cement and Concrete Composites, vol. 33, no. 6, pp. 644–652, 2011.
[29]  C. Andrade, V. Castelo, C. Alonso, and J. A. Gonzalez, “The determination of the corrosion rate of steel embedded in concrete by the polarization resistance and AC impedance methods,” in Proceedings of the STP 906, Corrosion of Rebar in Concrete, ASTM, Philadelphia, Pa, usa, 1984.
[30]  C. Boqi, H. Dinghai, G. Hengquan, and Z. Yinghao, “Ten-year field exposure tests on the endurance of reinforced concrete in harbor works,” Cement and Concrete Research, vol. 13, no. 5, pp. 603–610, 1983.

Full-Text

comments powered by Disqus

Contact Us

service@oalib.com

QQ:3279437679

微信:OALib Journal