Skip to main content
SpringerLink
Log in

Separation Phenomenon Occurring during the Charpy Impact Test of API X80 Pipeline Steels

  • Published:
Metallurgical and Materials Transactions A Aims and scope Submit manuscript

Abstract

A separation phenomenon occurring during the Charpy impact test of API X80 pipeline steels was investigated in the present study. A detailed microstructural analysis of fractured impact specimens showed that the band structure of bainite elongated along the rolling direction worked as prior initiation sites for separations, and that the number and length of the separations increased with the increasing volume fraction of bainite. In the steels having high work hardenability, tearing-shaped separations were found because the hammer-impacted region was seriously hardened during the impact test, which led to the reduction in the impact toughness. As the test temperature decreased, the tendency toward separations increased, but separations were not found when the cleavage fracture prevailed at very low temperatures. These findings suggested that the formation of bainite and secondary phases should be minimized for preventing or minimizing separations, because separations deteriorated the low-temperature impact toughness.

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
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

References

  1. M.K. Gräf, H.G. Hillenbrand, C.J. Heckmann, and K.A. Niederhoff: Proc. 13th Int. Offshore and Polar Engineering Conf., R. Ayer, I. Langen, R.H. Knapp, and J.S. Chung, eds., Honolulu, HI, 2003, vol. 4, pp. 97–104.

  2. R. Deny: Pipeline Technology, Elsevier, Amsterdam, The Netherlands, 2000, vol. I, pp. 1–116.

    Google Scholar 

  3. I. Tamura, H. Sekine, T. Tanaka, and C. Ouchi: Thermomechanical Processing of High-Strength Low-Alloy Steels, Butterworth & Co., Ltd., London, 1988, pp. 80–100.

    Google Scholar 

  4. I.D. Choi, D.M. Bruce, D.K. Matlock, and J.G.. Speer: Met. Mater. Int., 2008, vol. 14, pp. 139–47.

    Article  CAS  Google Scholar 

  5. D.W. Suh, C.S. Oh, and S.J. Kim: Met. Mater. Int., 2008, vol. 14, pp. 175–83.

    Google Scholar 

  6. F.T. Han, B.C. Hwang, D.W. Suh, Z.C. Wang, D.L. Lee, and S.J. Kim: Met. Mater. Int., 2008, vol. 14, pp. 667–73.

    CAS  Google Scholar 

  7. M. Diaz-Fuentes, A. Iza-Mendia, and I. Gutierrez: Metall. Mater. Trans. A, 2003, vol. 34A, pp. 2505–16.

    Article  ADS  CAS  Google Scholar 

  8. “ASTM E8m-08 Standard Test Methods for Tension Testing of Metallic Materials,” Annual Book of ASTM Standards, ASTM, West Conshohocken, PA, 2008, vol. 03.01, pp. 1–50.

  9. “ASTM E23-07ae1 Standard Test Method for Notched Bar Impact Testing of Metallic Materials,” Annual Book of ASTM Standards, ASTM, West Conshohocken, PA, 2007, vol. 03.01, pp. 1–27.

  10. W. Oldfield: ASTM Standardization News, 1975, Nov., pp. 24–29.

  11. C. Jing, D.W. Suh, C.S. Oh, Z.C. Wang, and S.J. Kim: Met. Mater. Int., 2007, vol. 13, pp. 13–20.

    Article  CAS  Google Scholar 

  12. T. Araki: Atlas for Bainitic Microstructures, ISIJ, Tokyo, 1992, pp. 1–165.

    Google Scholar 

  13. G. Krauss and S.W. Thompson: ISIJ, 1995, vol. 35, pp. 937–45.

    Article  CAS  Google Scholar 

  14. G. Baldi and G. Buzzichell: Met. Sci., 1978, vol. 12, pp. 459–72.

    CAS  Google Scholar 

  15. B. Hwang, Y.G. Kim, S. Lee, N.J. Kim, and J.Y. Yoo: Metall. Mater. Trans. A, 2005, vol. 36A, pp. 371–87.

    Article  CAS  Google Scholar 

  16. D.S. Dabkowski, D.J. Konkol, and M.F. Baldi: Met. Eng. Q., 1976, vol. 16, pp. 22–32.

    CAS  Google Scholar 

  17. D.N. Hawkins: Met. Technol., 1976, vol. 3, pp. 417–21.

    MathSciNet  Google Scholar 

  18. B.L. Bramfitt and A.R. Marder: Toughness Characterization and Specifications for HSLA and Structural Steels, AIME, New York, 1977, pp. 236–56.

    Google Scholar 

  19. S. Matsuda, Y. Kawashima, S. Sckiguchi, and M. Okamoto: Tetsu-to-Hagané, 1982, vol. 68, pp. 435–43.

    CAS  Google Scholar 

  20. M. Iino, H. Mimura, and N. Nomura: Trans. ISIJ, 1977, vol. 17, pp. 450–58.

    CAS  Google Scholar 

  21. J.F. Knott: Fundamentals of Fracture Mechanics, John Wiley & Sons, New York, NY, 1973, pp. 114–49.

    Google Scholar 

  22. J.W. Park, J.S. Kim, and I.G. Moon: J. Kor. Inst. Met. Mater., 1984, vol. 22, pp. 5–15.

    Google Scholar 

Download references

Acknowledgments

This work was supported by the National Research Laboratory Program (Grant No. ROA-2004-000-10361-0(2008)) funded by the Korea Science and Engineering Foundation (KOSEF) and by POSCO under Contract No. 2008Y220.

Author information

Authors and Affiliations

  1. Center for Advanced Aerospace Materials, Pohang University of Science and Technology, Pohang, 790-784, Korea

    Sang Yong Shin (Postdoctoral Research Associate), Seokmin Hong (Research Assistant) & Sunghak Lee (Professor)

  2. Materials Science and Engineering Department, Pohang University of Science and Technology, Pohang, Korea

    Sunghak Lee (Professor)

  3. Sheet Products & Process Research Group, Technical Research Laboratories, POSCO, Pohang, 790-785, Korea

    Jin-Ho Bae (Principal Researcher) & Kisoo Kim (Group Leader)

Authors
  1. Sang Yong Shin
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Seokmin Hong
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jin-Ho Bae
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Kisoo Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Sunghak Lee
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Sunghak Lee.

Additional information

Manuscript submitted December 10, 2008.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Shin, S.Y., Hong, S., Bae, JH. et al. Separation Phenomenon Occurring during the Charpy Impact Test of API X80 Pipeline Steels. Metall Mater Trans A 40, 2333–2349 (2009). https://doi.org/10.1007/s11661-009-9943-9

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11661-009-9943-9

Keywords

Search

Navigation