Journal of Materials Engineering and Performance

, Volume 23, Issue 12, pp 4230–4236 | Cite as

Microstructures and Mechanical Characteristics of a Medium Carbon Super-Bainitic Steel After Isothermal Transformation

Article
First Online:
Received:
Revised:

Abstract

The influence of isothermal treatments on microstructure, hardness, and tensile properties of a new designed medium carbon super-bainitic steel was studied by using the optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and mechanical property tests. The results show that the isothermal transformation temperature and holding time combine to determine the variations of microstructure and mechanical properties in the low temperature range of 140-260 °C. The size of bainitic laths is refined with the decrease in transformation temperature, but the bainitic transformation kinetic becomes lower. Longer treatment time can promote the transformation of complete bainite and also make the retained austenite more stable. The desired microstructure consisting of nanoscale carbide-free bainitic ferrite and thin film-like retained austenite located between the ferrite laths can be achieved at the temperature of 260 °C for 10 h, where the excellent combination of strength, ductility and hardness can be obtained.

Keywords

isothermal heat treatment microstructure property super-bainitic steel 
This is a preview of subscription content, log in to check access.

Notes

Acknowledgments

This work is supported by the National Natural Science Foundation of China (Grant No. 51171030).

References

  1. 1.
    J.M. Robertson, The Microstructure of Rapidly Cooled Steel, J. Iron Steel Inst., 1929, 119, p 391–424Google Scholar
  2. 2.
    M. Hillert, The Nature of Bainite, ISIJ Int., 1995, 35, p 1134–1140CrossRefGoogle Scholar
  3. 3.
    J.J. Wang, H.S. Fang, Z.G. Yang, and Y.K. Zheng, Fine Structure and Formation Mechanism of Bainite in Steels, ISIJ Int., 1995, 35, p 992–1000CrossRefGoogle Scholar
  4. 4.
    G. Xu, F. Liu, L. Wang, and H.J. Hu, A New Approach to Quantitative Analysis of Bainitic Transformation in a Superbainite Steel, Scr. Mater., 2013, 68, p 833–836CrossRefGoogle Scholar
  5. 5.
    A. Saha Podder and H.K.D.H. Bhadeshia, Thermal Stability of Austenite Retained in Bainitic Steels, Mater. Sci. Eng. A, 2010, 527, p 2121–2128CrossRefGoogle Scholar
  6. 6.
    F.G. Caballero, J. Chao, J. Cornide, C. Garcia-Mateo, M.J. Santofimia, and C. Capdevila, Toughness Deterioration in Advanced High Strength Bainitic Steels, Mater. Sci. Eng. A, 2009, 525, p 87–95CrossRefGoogle Scholar
  7. 7.
    F.G. Caballero, H.K.D.H. Bhadeshia, K.J.A. Mawella, D.G. Jones, and P. Brown, Design of Novel High Strength Bainitic Steels: Part 2, Mater. Sci. Technol., 2001, 17, p 517–522CrossRefGoogle Scholar
  8. 8.
    F. Hu, K.M. Wu, T.P. Hou, and A.A. Shirzadi, Tempering Stability of Retained Austenite in Nanostructured Dual Phase Steels, Mater. Sci. Technol., 2013, 29, p 947–953CrossRefGoogle Scholar
  9. 9.
    I. Lonardelli, M. Bortolotti, W. van Beek, L. Girardini, M. Zadra, and H.K.D.H. Bhadeshia, Powder Metallurgical Nanostructured Medium Carbon Bainitic Steel: Kinetics, Structure, and In Situ Thermal Stability Studies, Mater. Sci. Eng. A, 2012, 555, p 139–147Google Scholar
  10. 10.
    A. Misra, S. Sharma, S. Sangal, A. Upadhyaya, and K. Mondal, Critical Isothermal Temperature and Optimum Mechanical Behaviour of High Si-Containing Bainitic Steels, Mater. Sci. Eng. A, 2012, 558, p 725–729CrossRefGoogle Scholar
  11. 11.
    H.K.D.H. Bhadeshia, Bainite in Steels, IOM Commercial Ltd., London, 2001Google Scholar
  12. 12.
    F.G. Caballero, M.K. Miller, S.S. Babu, and C. Garcia-Mateo, Atomic Scale Observations of Bainite Transformation in a High Carbon High Silicon Steel, Acta Mater., 2007, 55, p 381–390CrossRefGoogle Scholar
  13. 13.
    O. Kazum, M. Bobby Kannan, H. Beladi, I.B. Timokhina, P.D. Hodgson, and S. Khoddam, Aqueous Corrosion Performance of Nanostructured Bainitic Steel, Mater. Des., 2014, 54, p 67–71CrossRefGoogle Scholar
  14. 14.
    H. Huang, M.Y. Sherif, and P.E.J. Rivera-Dı′az-del-Castillo, Combinatorial Optimization of Carbide-Free Bainitic Nanostructures, Acta Mater., 2013, 61, p 1639–1647CrossRefGoogle Scholar
  15. 15.
    A. Barbacki and E. Mikolajski, Optimization of Heat Treatment Conditions for Maximum Toughness of High Strength Silicon Steel, J. Mater. Process. Technol., 1998, 78, p 18–23CrossRefGoogle Scholar
  16. 16.
    C. Garcia-Mateo, F.G. Caballero, and H.K.D.H. Bhadeshia, Acceleration of Low-Temperature Bainite, ISIJ Int., 2003, 43, p 1821–1825CrossRefGoogle Scholar
  17. 17.
    M.N. Yoozbashi, S. Yazdani, and T.S. Wang, Design of a New Nanostructured, High-Si Bainitic Steel with Lower Cost Production, Mater. Des., 2011, 32, p 3248–3253CrossRefGoogle Scholar
  18. 18.
    H. Amel-Farzad, H.R. Faridi, F. Rajabpour, A. Abolhasani, Sh Kazemi, and Y. Khaledzadeh, Developing Very Hard Nanostructured Bainitic Steel, Mater. Sci. Eng. A, 2013, 559, p 68–73CrossRefGoogle Scholar
  19. 19.
    L. Qian, Q. Zhou, F. Zhang, J. Meng, M. Zhang, and Y. Tian, Microstructure and Mechanical Properties of a Low Carbon Carbide-Free Bainitic Steel CO-Alloyed with Al and Si, Mater. Des., 2012, 39, p 264–268CrossRefGoogle Scholar
  20. 20.
    J. Cornide, C. Garcia-Mateo, C. Capdevila, and F.G. Caballero, An Assessment of the Contributing Factors to the Nanoscale Structural Refinement of Advanced Bainitic Steels, J. Alloy Compd., 2013, 577, p S43–S47CrossRefGoogle Scholar
  21. 21.
    F.G. Caballero and H.K.D.H. Bhadeshia, Very Strong Bainite, Curr. Opin. Solid State Mater. Sci., 2004, 8, p 251–257CrossRefGoogle Scholar
  22. 22.
    L.C. Chang, Microstructures and Reaction Kinetics of Bainite Transformation in Si-Rich Steels, Mater. Sci. Eng. A, 2004, 368, p 175–182CrossRefGoogle Scholar
  23. 23.
    M. Zhang, T.S. Wang, Y.H. Wang, J. Yang, and F.C. Zhang, Preparation of Nanostructured Bainite in Medium-Carbon Alloy Steel, Mater. Sci. Eng. A, 2013, 568, p 123–126CrossRefGoogle Scholar
  24. 24.
    F.G. Caballero, S. Allain, J. Cornide, J.D. Puerta Velásquez, C. Garcia-Mateo, and M.K. Miller, Design of Cold Rolled and Continuous Annealed Carbide-Free Bainitic Steels for Automotive Application, Mater. Des., 2013, 49, p 667–680CrossRefGoogle Scholar
  25. 25.
    S.V. Radcliffe and E.C. Rollason, The Kinetics of the Formation of Bainite in High Purity Fe-C Alloys, J. Iron Steel Inst., 1959, 191, p 56–65Google Scholar
  26. 26.
    D.P. Koistinen and R.E. Marburger, A General Equation For Austenite-Martensite Transformation in Pure Carbon Steels, Acta Metall., 1959, 7, p 59–60CrossRefGoogle Scholar
  27. 27.
    C. Garcia-Mateo, F.G. Caballero, and H.K.D.H. Bhadeshia, Development of Hard Bainite, ISIJ Int., 2003, 43, p 1238–1243CrossRefGoogle Scholar
  28. 28.
    M.-X. Zhang and P.M. Kelly, Crystallography of Carbide-Free Bainite in a Hard Bainite Steel, Mater. Sci. Eng., A, 2006, 438–440, p 272–275CrossRefGoogle Scholar
  29. 29.
    H.K.D.H. Bhadeshia and A.R. Waugh, Bainite: An Atom-Probe Study of the Incomplete Reaction Phenomenon, Acta Metall., 1982, 30, p 775–784CrossRefGoogle Scholar
  30. 30.
    B. Avishan, S. Yazdani, and S.H. Nedjad, Toughness Variations in Nanostructured Bainitic Steels, Mater. Sci. Eng., A, 2012, 548, p 106–111CrossRefGoogle Scholar

Copyright information

© ASM International 2014

Authors and Affiliations

  1. 1.Key Laboratory of Advanced Structural Materials, Ministry of EducationChangchun University of TechnologyChangchunChina
  2. 2.College of Mechanical EngineeringYangzhou UniversityYangzhouChina

Personalised recommendations