Advertisement

Russian Metallurgy (Metally)

, Volume 2019, Issue 10, pp 932–938 | Cite as

Formation of Z-Phase Particles in a Martensitic 9% Cr Steel during Creep at 650°C and Their Influence on the Creep

  • A. E. FedoseevaEmail author
  • I. S. Nikitin
  • N. R. Dudova
  • R. O. Kaibyshev
PHYSICAL FOUNDATIONS OF STRENGTH AND PLASTICITY
  • 6 Downloads

Abstract—The mechanism of the nucleation of Z-phase (CrVN) particles in a martensitic 10Kh9K3V2MFBR steel (9 wt % Cr) during creep at a temperature of 650°C is studied. The nucleation mechanism of Z-phase particles at a creep temperature of 650°C is found to be restructuring of the crystal lattice of V(C,N) carbonitrides due to the diffusion of chromium atoms. The transformation of nanosized V(C,N) carbonitrides into Z-phase particles is shown to weakly contribute to the structural degradation in the steel and not to cause its premature fracture during creep at 650°C if at least 50% V(C,N) carbonitrides of the initial volume fraction of these particles are retained (even at a large average size (≈200 nm) of Z-phase particles).

Keywords: martensitic high-temperature steel creep M(C,N) carbonitrides Z phase phase transformation 

Notes

ACKNOWLEDGMENTS

We thank the Technologies and Materials core facility of Belgorod State University for supplying their equipment for the structural investigations.

FUNDING

This work was supported by the Russian Foundation for Basic Research, project no. 18-38-00002 mol_a.

REFERENCES

  1. 1.
    T. U. Kern, M. Staubli, and B. Scarlin, “The European efforts in material development for 650°C USC power plants—COST522,” ISIJ Int. 42, 1515–1519 (2002).Google Scholar
  2. 2.
    F. Abe, T. U. Kern, and R. Viswanathan, Creep-Resistant Steels (Woodhead Publishing, Cambridge, 2008).CrossRefGoogle Scholar
  3. 3.
    H. K. Danielsen, P. E. Di Nunzio, and J. Hald, “Kinetics of Z-phase precipitation in 9 to 12 pct Cr steels,” Metall. Mater. Trans. A 44, 2445–2452 (2013).CrossRefGoogle Scholar
  4. 4.
    A. Strang and V. Vodarek, “Z phase formation in martensitic 12CrMoVNb steel,” J. Mater. Sci. Techn. 12, 552–556 (1996).CrossRefGoogle Scholar
  5. 5.
    K. Suzuki, S. Kumai, H. Kushima, K. Kimura, and F. Abe, “Heterogeneous recovery and precipitation of Z-phase during long term creep deformation of modified 9Cr–1Mo steel,” Tetsu to Hagane 86, 550–557 (2000).CrossRefGoogle Scholar
  6. 6.
    K. Suzuki, S. Kumai, H. Kushima, K. Kimura, and F. Abe, “Precipitation of Z-phase and precipitation sequence during creep deformation of mod. 9Cr–1Mo steel,” Tetsu to Hagane 89, 691–698 (2003).CrossRefGoogle Scholar
  7. 7.
    V. Sklenicka, K. Kucharova, M. Svoboda, L. Kloc, J. Bursik, and A. Kroupa, “Long-term creep behavior of 9–12% Cr power plant steels,” Mater. Characteriz. 51, 35–48 (2003).Google Scholar
  8. 8.
    I. Letofsky-Papst, P. Warbichler, F. Hofer, E. Letofsky, and H. Cerjak, “On the occurrence of Z-phase in a creep-tested 10% Cr steel,” Z. Metallkd. 95, 18–21 (2004).Google Scholar
  9. 9.
    H. K. Danielsen and J. Hald, “On the nucleation and dissolution process of Z-phase Cr(V,Nb)N in martensitic 12% Cr steels,” Mater. Sci. Eng., A 505, 169–177 (2009).Google Scholar
  10. 10.
    H. K. Danielsen, J. Hald, and M. A. J. Somers, “Atomic resolution imaging of precipitate transformation from cubic TaN to tetragonal CrTaN,” Scr. Mater. 66, 261–264 (2012).CrossRefGoogle Scholar
  11. 11.
    H. K. Danielsen, S. Kadkhodazadeh, F. B. Grumsen, and M. A. J. Somers, “New amorphous interface for precipitate nitrides in steel,” Philos. Mag. 94, 2339–2349 (2014).CrossRefGoogle Scholar
  12. 12.
    H. K. Danielsen, “Precipitation process of Z-phase in 9–12% Cr steels,” in Proceedings of 7th International Conference on Advances in Materials Technology for Fossil Power Plants (ASM Int., Waikoloa, 2013), pp. 1104–1115.Google Scholar
  13. 13.
    H. K. Danielsen, “Review of Z phase precipitation in 9–12 wt % Cr steels,” J. Mater. Sci. Techn. 32, 126–137 (2016).Google Scholar
  14. 14.
    R. O. Kaibyshev, V. N. Skorobogatykh, and I. A. Shchenkova, “Z-phase formation and the prospects of application of martensitic 11% Cr steels for operation at temperatures above 590°C,” Metalloved. Term. Obrab. Met., No. 3, 4–14 (2010).Google Scholar
  15. 15.
    A. Fedoseeva, N. Dudova, U. Glatzel, and R. Kaibyshev, “Effect of W on tempering behaviour of a 3% Co modified P92 steel,” J. Mater. Sci. 51, 9424–9439 (2016).Google Scholar
  16. 16.
    A. Fedoseeva, N. Dudova, and R. Kaibyshev, “Creep strength breakdown and microstructure evolution in a 3% Co modified P92 steel,” Mater. Sci. Eng., A 654, 1–12 (2016).Google Scholar
  17. 17.
    F. Abe, “Creep behavior, deformation mechanisms and creep life of mod. 9Cr–1Mo steel,” Metall. Mater. Trans. A 46, 5610–5625 (2015).CrossRefGoogle Scholar
  18. 18.
    A. Fedoseeva, N. Dudova, and R. Kaibyshev, “Creep behavior and microstructure of a 9Cr–3Co–3W martensitic steel,” J. Mater. Sci. 52, 2974–2988 (2017).CrossRefGoogle Scholar
  19. 19.
    L. Cipolla, H. K. Danielsen, D. Venditti, P. E. Di Nunzio, J. Hald, and M. A. J. Somers, “Conversion of MX nitrides to Z-phase in a martensitic 12% Cr steel,” Acta Mater. 58, 669–679 (2010).Google Scholar

Copyright information

© Pleiades Publishing, Ltd. 2019

Authors and Affiliations

  • A. E. Fedoseeva
    • 1
    Email author
  • I. S. Nikitin
    • 1
  • N. R. Dudova
    • 1
  • R. O. Kaibyshev
    • 1
  1. 1.Belgorod State UniversityBelgorodRussia

Personalised recommendations