Skip to main content

Effect of Nitrogen on Transformation Behaviors and Microstructure of V-N Microalloyed Steel

  • Conference paper
HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015

Abstract

Multi-pass deformation simulation tests were performed on V-N microalloyed steels with different nitrogen addition by using a Gleeble-3800 thermo-mechanical simulator and the corresponding continuous cooling transformation (CCT) diagrams were determined by thermal dilation method and metallographic method. The deformed austenite transformation behavior and resultant microstructure of the tested steels were studied. Furthermore, the effect of nitrogen addition on the transformation behavior and microstructure evolution was analyzed. The results show that the transformed microstructures in the three tested steels are ferrite, pearlite and bainite respectively while the transformation temperatures are not the same. For the two tested steel with higher nitrogen additions, higher ferrite start temperature and critical cooling rates are observed. Furthermore, an increase in nitrogen addition leads to increasing quantities of ferrite and the transformed ferrite is smaller in size. The hardness test results reveal that the hardness number increases with increasing nitrogen addition at low cooling rate while the value tends to be smaller due to increasing nitrogen addition at high cooling rate. Therefore, the hardness number of the steel with high nitrogen addition is not so sensitive to cooling rate as that of the steel with low nitrogen addition.

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

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 319.00
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Sun, Z. Q., Li, L. F., Sha, Q. Y, “Refinement of coarse grained austenite in Nb-V-Ti microalloyed steel during roughing rolling,” Ironmaking & Steelmaking, 42 (2015) 74–80.

    Article  Google Scholar 

  2. Zhou G F. et al, “ Effect of copper and boron content on strain-induced Nb (C, N) precipitation in ULCB steels at hot deformation temperature,” Acta Metallurgica Sinica: English Letters, 13 (2000), 623–627.

    Google Scholar 

  3. Wang Z. F et al, “Effect of Nb on Continuous Cooling Transformation Behavior of Low Carbon Microalloyed Steel,” Journal of Northeastern University, 35(2014), 1117–1119.

    Google Scholar 

  4. Sage A M., “Effect of Vanadium, Nitrogen and Auminium on the Mechanical Properties of Reinforcing Bar Steels,” Metals Technology, 2(1976), 65–70.

    Article  Google Scholar 

  5. Zajac S, Lagneborg R and Siwechi T, “The Role of Nitrogen in Mcroalloyed Steels” (Paper presented at Mcroalloying’95 Proceeding of International conference, Pittsburgh, PA,ISS,1995) , 321–340.

    Google Scholar 

  6. Lagneborg R et al., “The Role of Vanadium in Mcroalloyed Steels,” Scandinavian Journal of Metallurgy, 28(5)(1999), 186–241.

    Google Scholar 

  7. Hutchinson Bevis, “Different Roles for Vanadium as a Mcroalloying Element in Structural Steels,” Journal of Iron and Steel Research International, 18(2011), 29–38.

    Article  Google Scholar 

  8. S.F Medina, M. Gomez, L. Rancel, “Grain refinement by intragranular nucleation of ferrite in a high nitrogen content vanadium microalloyed steel,” Scr. Mater. 58 (2008), 1110–1113.

    Article  Google Scholar 

  9. C.PReip, S.Shanmugamb and R.D.K. Msra, “High strength microalloyed CMn(V-Nb-Ti) and CMn(V-Nb) pipeline steels processed through CSP thin-slab technology: Mcrostructure, precipitation and mechanical properties,” Materials Science and Engineering A, 424 (2006), 307–317.

    Article  Google Scholar 

  10. Kimura T, et al., “Ferrite grain refinement through intra-granular ferrite transformation on VN precipitation in TMCP of HSLA steel” (Paper presented at Thermec’97 Conference Proceedings, Wollongong, Australia, Published by TMS, 1997), 645–651.

    Google Scholar 

  11. Zhao Baochun et al., “Effect of Thermo-Mechanical Process on Phase Transformation Behaviors of V-Ti-N Mcroalloyed Steel,” Steel Research Int., 83 (2012), 328–332.

    Article  Google Scholar 

  12. Gao F et al, “Phase Transformation Characteristics of Vanadium Mcroalloying Low Carbon Bainitic Steel in Continuous Cooling Process,” Journal of Iron and Steel Research, 23(2011), 40–44.

    Google Scholar 

  13. Kimura T, “Heavy Gauge H-shapes With Excellent Seismic Resistance for Building Structures Produced by the Third Generation TMCP” (Paper presented at International Symposium on Steel for Fabricated Structures Conference Proceedings, ASM International, Materials Park, OHUSA. 1999), 1–4.

    Google Scholar 

  14. Baochun Zhao et al., “Research on the Static Recrystallization and Precipitation Behaviors of a V-N Mcroalloyed Steel,” Advances in Materials Science and Engineering, vol. 2013, Article ID 390

    Google Scholar 

  15. Gong Weimi, Yang Caifu and Zhan Yongquan, “Grain Refinement in V-N Steel,” Journal of Iron and Steel Research, 18 (2006), 49–53.

    Google Scholar 

  16. Jun Hu et al, “Microstructure and mechanical properties of TMCP heavy plate microalloyed steel,” Materials Science and Engineering, A, 607(2014), 122–131.

    Article  Google Scholar 

  17. Khlestov V M, Konopleva E V and Mcqueen H J, “Kinetics of Austenite Transformation During Thermo mechanical Processes,” Canadian Metallurgical Quarterly, 37(2)(1998), 75.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

Copyright information

© 2016 TMS

About this paper

Cite this paper

Zhao, B., Zhao, T., Li, G., Lu, Q. (2016). Effect of Nitrogen on Transformation Behaviors and Microstructure of V-N Microalloyed Steel. In: HSLA Steels 2015, Microalloying 2015 & Offshore Engineering Steels 2015. Springer, Cham. https://doi.org/10.1007/978-3-319-48767-0_11

Download citation

Publish with us

Policies and ethics