Skip to main content
SpringerLink
Log in

Study on Step-Annealing Heat Treatment on Properties of Grade 6A Duplex Stainless Steels of ASTM A890

  • Original Contribution
  • Published:
Journal of The Institution of Engineers (India): Series D Aims and scope Submit manuscript

Abstract

Improvement in properties of duplex steel grade 6A is always a thrust area of interest from application point of view and in that heat treatment plays an important role. The precipitations and phase ratio are key factor in determining the properties of super duplex stainless steels. The furnace cooling or step-annealing at lower temperature than normal annealing temperature and for a short time was not included in ASTM A890-18 version has now been added in 18a version for grade 6A like other duplex grades. For studying effect of step annealing on the phase ratio and properties of SDSS, the specimens were soaked at temperatures in the range of 1130–1190 °C and next furnace cooled to 1100 °C and holding for 15 min followed by water quenching. The micrograph of specimen directly quenched from 1100 °C revealed high ferrite content whereas the micrograph of the specimens subjected to step-annealing process revealed higher austenite content with more equiaxed structure. The step-annealing increased the austenite percentage and improved the impact toughness by 24%. However, the hardness of the specimen reduced as the step-annealing temperature increased. The polarization curves revealed a cathodic shift in the curve of the specimen directly quenched from 1100 °C compared to the step-annealed specimens. The reason for this reduction was investigated by special etching techniques, electron microscopy and energy-dispersive spectroscopy. Undissolved Cr2N precipitations were observed in the specimen directly quenched from 1100 °C, leading to the reduction in corrosion resistance.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

References

  1. J. Charles, P. Chemelle, The history of duplex developments, nowadays DSS properties and duplex market future trends, in 8th Duplex Stainless Steel Conference, Breaune, France (2010), pp. 13–15

  2. R.N. Gunn, Duplex Stainless Steels: Microstructure, Properties and Applications, 1st edn. (Abington Publishing, Cambridge, 1997)

    Book  Google Scholar 

  3. M. Theofanous, L. Gardner, Experimental and numerical studies of lean duplex stainless steel beams. J. Constr. Steel Res. 66, 816–825 (2010)

    Article  Google Scholar 

  4. H. Hwang, Y. Park, Effects of heat treatment on the phase ratio and corrosion resistance of duplex stainless steel. Mater. Trans. 50, 1548–1552 (2009)

    Article  Google Scholar 

  5. M. Martins, L.C. Casteletti, Heat treatment temperature influence on ASTM A890 GR 6A superduplex stainless steel microstructure. Mater. Charact. 55, 225–233 (2005)

    Article  Google Scholar 

  6. International Molybdenum Association (IMOA), Practical Guidelines for the Fabrication of Duplex Stainless Steel, 3rd edn. (International Molybdenum Association (IMOA), London, 2014)

    Google Scholar 

  7. Z. Zhang, H. Zhang, H. Jun, X. Qi, Y. Bian, A. Shen, P. Xu, Y. Zhao, Microstructure evolution and mechanical properties of briefly heat treated SAF 2507 super duplex stainless steel welds. Constr. Build. Mater. 168, 338–345 (2018)

    Article  Google Scholar 

  8. H. Siurin, Fracture toughness properties of duplex stainless steels, Ph.D thesis, Royal Institute of Technology, Stockholm, Sweden, 2006

  9. J. Stolarz, J. Foct, Specific features of two phase alloys response to cyclic deformation. Mater. Sci. Eng. A 319, 501–505 (2001)

    Article  Google Scholar 

  10. J.-B. Vogt, Fatigue properties of high nitrogen steels. Mater. Process. Technol. 117, 364–369 (2001)

    Article  Google Scholar 

  11. A. Mateo, L. Llanes, N. Akdut, M. Anglada, High cycle fatigue behaviour of a standard duplex stainless steel plate and bar. Mater. Sci. Eng. A 319, 516–520 (2001)

    Article  Google Scholar 

  12. 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, 1994)

    Google Scholar 

  13. J.R. Davis, Structure and Property Relationships of Iron and Steel Metals Handbook 361, desk edition, 2nd edn. (ASM International, 1998), pp. 153–173

  14. G. Argandona, J.F. Palacio, C. Berlanga, M.V. Biezma, P.J. Rivero, J. Pena, R. Rodriguez, Effect of temperature of mechanical properties of austenite, ferrite and sigma phases of duplex stainless steels using hardness, micro-hardness and nano-indentation techniques. Metals 7(6), 219 (2017). https://doi.org/10.3390/met7060219

    Article  Google Scholar 

  15. M. Gholami, M. Hoseinpoor, M.H. Moayed, A statistical study on the effect of annealing temperature on pitting corrosion resistance of 2205 duplexstainless steel. Corros. Sci. 94, 156–164 (2015)

    Article  Google Scholar 

  16. S. Hertzman, W. Roberts, M. Lindenmo, Microstructure and Properties of Nitrogen Alloyed Stainless Steel After Welding Treatments (Duplex Stainless steels ´86, Hague, 1986), pp. 257–263

    Google Scholar 

  17. American Society for Testing and Materials. ASTM A890/A890M—91. Standard practice for castings, iron–chromium– nickel–molybdenum corrosion resistant, duplex (austenitic/ferritic) for general application. ASTM International (1999)

  18. N. 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)

    Article  Google Scholar 

  19. S. Wessman, M. Selleby, Evaluation of austenite reformation in duplex stainless steel weld metal using computational thermodynamics. Weld World 58, 217–224 (2014)

    Article  Google Scholar 

  20. M. Eskandari, M. Yeganeh, M. Motamedi, Investigation in the corrosion behaviour of bulk nanocrystalline 316L austenitic stainless steel in NaCl solution. Micro Nano Lett. 7, 380–383 (2012)

    Article  Google Scholar 

  21. H. Ha, H. Kwon, Effects of Cr2N on the pitting corrosion of high nitrogen stainless steels. Electrochem. Acta 52, 2175–2180 (2007)

    Article  Google Scholar 

  22. P. Paulraj, R. Garg, Effect of intermetallic phases on corrosion behaviour and mechanical properties of duplex stainless steel and super duplex stainless steel. Adv. Sci. Technol. Res. J. 9, 87–105 (2015)

    Article  Google Scholar 

Download references

Acknowledgements

Authors wish to acknowledge the management and staff of Peekay steel castings (P) Ltd. for the support they extended toward the completion of this project.

Author information

Authors and Affiliations

  1. Research and Development (Metallurgy), Peekay Steel Castings Pvt. Ltd., Calicut, India

    P. Nithin Raj & B. Raha

Authors
  1. P. Nithin Raj
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. B. Raha
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to P. Nithin Raj.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Nithin Raj, P., Raha, B. Study on Step-Annealing Heat Treatment on Properties of Grade 6A Duplex Stainless Steels of ASTM A890. J. Inst. Eng. India Ser. D 102, 185–193 (2021). https://doi.org/10.1007/s40033-020-00245-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s40033-020-00245-y

Keywords

Search

Navigation