Effect of Austenite Reformation on Localized Corrosion Resistance of Hyper-Duplex Stainless Steel in Hot Chloride Solution

  • P. Nithin RajEmail author
  • Anandu P. Sivan
  • K. Sekar
  • M. A. Joseph


The materiality of duplex stainless steels for deep-sea applications, where high corrosive conditions prevail, was studied in the present work. The effect of annealing temperature on the phase balance of the new hyper-duplex grade and subsequent variation in their corrosion resistance at hot chloride environments were estimated. ASTM A890 grade 7A samples were soaked at 1130 °C, 1160 °C, and 1190 °C and furnace-cooled till 1060 °C followed by water quenching. Electron microscope and optical micrograph images confirmed the decrease in austenite with the rise in solutionizing temperature; but on slow cooling, major austenite reformation takes place. Energy-dispersive spectroscopy (EDS) and line-scan methods were used to find out the distribution of constituent alloying elements. The migration of Cr and Mo to the austenite phase occurred as a result of the heat-treatment processes. Potentiodynamic polarization technique was conducted at different temperatures of 30 °C, 40 °C, 50 °C, and 60 °C on all heat-treated samples. At higher temperatures, corrosion resistance improved with an increase in austenite percentage. Optical images of the corroded samples showed the metastable pit growth with an increase in chloride medium temperature.


duplex stainless steel corrosion NaCl annealing temperature austenite reformation PREN 



The authors are much indebted to Peekay Steels Pvt Ltd for casting the required compositions and their prompt services after that. We are also obliged to Dr. M Ravi of NIIST CSIR Trivandrum for all the assistance and support bestowed on for EDS and SEM analysis.


  1. 1.
    E. Edwards, D. Hodgkinson, M. Maxfield, Effect of chemistry and heat treatment on the pitting corrosion resistance of three duplex stainless steel alloys. Int. J. Metalcast. 10, 118–121 (2016)CrossRefGoogle Scholar
  2. 2.
    K. Göransson, M.L. Nyman, M. Holmquist, E. Gomes, Sandvik SAF 2707 HD ® (UNS S32707): a hyper-duplex stainless steel for severe chloride containing environments. Rev. Métall. Paris 104, 411–417 (2007)CrossRefGoogle Scholar
  3. 3.
    V. Muthupandi, P.B. Srinivasan, S.K. Seshadri, S. Sundaresan, Effect of weld metal chemistry and heat input on the structure and properties of duplex stainless steels. Mater. Sci. Eng. A 358, 9–15 (2003)CrossRefGoogle Scholar
  4. 4.
    T. Wan, N. Xiao, H. Shen, X. Yong, The effect of chloride ions on the corroded surface layer of 00Cr22Ni5Mo3N duplex stainless steel under cavitation. Ultrason. Sonochem. 33, 1–9 (2016)CrossRefGoogle Scholar
  5. 5.
    G.S. Frankel, Pitting corrosion of metals. J. Electrochem. Soc. 145, 2186–2198 (1998)CrossRefGoogle Scholar
  6. 6.
    M.M. Stephen, D. Douglas, J.H. Dunn, Metallurgical examination of cooling water equipment failures, Ashland Specialty Chemical Company, drew industrial Analyst (2005)Google Scholar
  7. 7.
    R. Tolulope, C. Akintoye, Corrosion behaviour of S43035 ferritic stainless steel in hot sulphate/chloride solution. J. Mater. Res. Technol. 7, 1–9 (2018)CrossRefGoogle Scholar
  8. 8.
    H.M. Ezuber, A. El-houd, F. El-shawesh, Effects of sigma phase precipitation on seawater pitting of duplex stainless steel 207, 268–275 (2007)Google Scholar
  9. 9.
    M. Martins, L.C. Casteletti, Microstructural characteristics and corrosion behavior of a super duplex stainless steel casting. Mater. Charact. 60, 150–155 (2009)CrossRefGoogle Scholar
  10. 10.
    B. Josefsson, J.O. Nilsson, A. Wilson, Phase transformations in DSS and the relation between continuous cooling and isothermal heat treatment. Proc. Conf. Duplex Stainless Steels ‘91, Les Editions de Physique, Les Ulis, 67–78 (1991)Google Scholar
  11. 11.
    P. Paulraj, R. Garg, Effect of intermetallic phases on corrosion behavior and mechanical properties of duplex stainless steel and super-duplex stainless steel. Adv. Sci. Technol. Res. J. 9, 87–105 (2015)CrossRefGoogle Scholar
  12. 12.
    H. Tan, Y. Jiang, B. Deng, T. Sun, J. Xu, Effect of annealing temperature on the pitting corrosion resistance of super duplex stainless steel UNS S32750. Mater. Charact. 60, 1049–1054 (2009)CrossRefGoogle Scholar
  13. 13.
    L.Q. Guo, M. Li, X.L. Shi, Y. Yan, X.Y. Li, L.J. Qiao, Effect of annealing temperature on the corrosion behavior of duplex stainless steel studied by in situ techniques. Corros. Sci. 53, 3733–3741 (2011)CrossRefGoogle Scholar
  14. 14.
    L. Zhang, W. Zhang, Y. Jiang, B. Deng, D. Sun, J. Li, Influence of annealing treatment on the corrosion resistance of lean duplex stainless steel 2101. Electrochim. Acta 54, 5387–5392 (2009)CrossRefGoogle Scholar
  15. 15.
    S. Wessman, M. Selleby, Evaluation of austenite reformation in duplex stainless steel weld metal using computational thermodynamics. Weld World 58, 217–224 (2014)CrossRefGoogle Scholar
  16. 16.
    T.A. Palmer, J. Elmer, S.S. Babu, Observations of ferrite/austenite transformations in the heat affected zone of 2205 duplex stainless steel spot welds using time resolved X-ray diffraction. Mater. Sci. Eng. A 374, 307–321 (2004)CrossRefGoogle Scholar
  17. 17.
    S. Hertzman, The influence of nitrogen on microstructure and properties of highly alloyed stainless steel welds. ISIJ Int. 41, 580–589 (2001)CrossRefGoogle Scholar
  18. 18.
    H. Sieurin, R. Sandström, Austenite reformation in the heat-affected zone of duplex stainless steel 2205. Mater. Sci. Eng. A 418, 250–256 (2006)CrossRefGoogle Scholar
  19. 19.
    H. Hoffmeister, G. Lothongkum, Quantitative Effects of Nitrogen Contents and Cooling Cycles on Transformation, Chromium Nitride pRecipitation and Pitting Corrosion After Weld Simulation of Duplex Stainless Steels, Duplex Stainless steels ‘94 (Glasgow, Scotland, 1994)Google Scholar
  20. 20.
    H. Sieurin, (2006), Fracture toughness properties of duplex stainless steels, Ph.D. thesis, Royal institute of technology, Stockholm, SwedenGoogle Scholar
  21. 21.
    H. Haghdadi, P. Cizek, P.D. Hodgson, H. Beladi, Microstructure dependence of impact toughness in duplex stainless steels. Mater. Sci. Eng. A 745, 369–378 (2019)CrossRefGoogle Scholar
  22. 22.
    S. Atamert, J.E. King, Super duplex stainless steels. Part 1. Heat affected zone microstructures. Mater. Sci. Technol. 8, 869–911 (1992)CrossRefGoogle Scholar
  23. 23.
    Y. Guo, J. Hu, J. Li, L. Jiang, T. Liu, Y. Wu, Effect of annealing temperature on the mechanical and corrosion behavior of a newly developed novel lean duplex stainless steel. Materials 7, 6604–6614 (2014)CrossRefGoogle Scholar
  24. 24.
    M.B. Fathy, W.A. Ghanem, Effect of nitrogen on the corrosion behavior of austenitic stainless steel in chloride solutions. Mater. Lett. 59, 3311–3314 (2005)CrossRefGoogle Scholar
  25. 25.
    A. Kosmač, Stainless Steels at High Temperatures, Materials and Application series, Volume 18. Accessed May 2019
  26. 26.
    G.C. Palit, V. Kain, H.S. Gadiyar, Electrochemical investigations of pitting corrosion in nitrogen-bearing type 316LN stainless steel. Corrosion 49, 977–991 (1993)CrossRefGoogle Scholar
  27. 27.
    H.B. Li, Z. Jiang, H. Feng, S. Zhang, P. Han, W. Zhang, G.P. Li, G.W. Fan, Effect of temperature on the corrosion behavior of super austenitic stainless steel S32654 in polluted phosphoric acid. Int. J. Electrochem. Sci. 10, 4832–4848 (2015)Google Scholar
  28. 28.
    St Matsch, H. Bohni, Influence of temperature on the localized corrosion of stainless steels. Russ. J. Electrochem 36, 1122–1128 (2000)CrossRefGoogle Scholar

Copyright information

© American Foundry Society 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringNational Institute of TechnologyCalicutIndia

Personalised recommendations