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Influence of Composition and Hot Rolling on the Subsurface Microstructure and Bendability of Ultrahigh-Strength Strip

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Abstract

The effect of subsurface microstructure on the bendability of three 8-mm-thick low-alloyed hot-rolled and direct-quenched ultrahigh-strength strip steels with yield strengths in the range 800 to 1100 MPa has been investigated. Rolling to lower finish rolling temperatures increased austenite pancaking, leading to the formation of ferritic/granular bainitic subsurface microstructures that are softer than the upper bainitic microstructures found with higher finish rolling temperature. In addition, increased austenite pancaking was found to increase the intensities of ~{112}〈111〉α and ~{110}〈112〉α to {110}〈111〉α texture components in the surface layers, especially in upper bainitic microstructures. It is shown that the bendability of ultrahigh-strength steels is governed by subsurface hardness and crystallographic texture. Bendability was found to be related to mean microhardness 0.1 to 0.4 mm below the surface, such that excellent bendability was achieved with a relatively soft subsurface layer down to a depth of 0.4 mm, i.e., 5 pct of the sheet thickness. Intense ~{112}〈111〉α texture combined with upper bainite containing MA islands in the subsurface region is shown to be detrimental to bendability when the bend axis is perpendicular to the rolling direction probably as a result of geometrical softening combined with high hardness.

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References

  1. H. Asahi, E. Tsuru, T. Hara, M. Sugiyama, Y. Terada, H. Shinada, S. Ohkita, H. Morimoto, N. Doi, M. Murata, H. Miyazaki, E. Yamashita, T. Yoshida, N. Ayukawa, H. Akasaki, M. L. Macia, C. W. Petersen, J. Y. Koo, N. V. Bangaru, and M. J. Luton: Int. J. Offshore Polar Eng., 2004, vol. 14, pp. 36–41.

    Google Scholar 

  2. M. Hemmilä, R. Laitinen, T. Liimatainen, and D.A. Porter: in Proc. 1st Int. Conf. “Super-High Strength Steels” (Associazone Italiana di Metallurgica – AIM, Rome, 2005).

  3. A. J. Kaijalainen, P. P. Suikkanen, T. J. Limnell, L. P. Karjalainen, J. I. Kömi, and D. A. Porter: J. Alloys Compd., 2013, vol. 577, pp. S642–48.

    Article  Google Scholar 

  4. A. J. Kaijalainen, P. Suikkanen, L. P. Karjalainen, J. J. Jonas: Metall. Mater. Trans. A, 2014, vol. 45, pp. 1273–83.

    Article  Google Scholar 

  5. J. Heikkala and A. Väisänen: in Proc. 11th Bienn. Conf. Eng. Syst. Des. Anal. (2012), pp. 1–13.

  6. D. Rèche, T. Sturel, O. Bouaziz, A. Col, and A. F. Gourgues-Lorenzon: Mater. Sci. Eng. A, 2011, vol. 528, pp. 5241–50.

    Article  Google Scholar 

  7. C. Soyarslan, M. Malekipour Gharbi, and A. E. Tekkaya: Int. J. Solids Struct., 2012, vol. 49, pp. 1608–26.

    Article  Google Scholar 

  8. M. Kaupper and M. Merklein: CIRP Ann. - Manuf. Technol., 2013, vol. 62, pp. 247–50.

    Article  Google Scholar 

  9. M. Liimatainen: The Effect of Microstructure on Bendability of Ultra-High Strength Steels, Tampere University of Technology, 2015.

  10. A. J. Kaijalainen, P. P. Suikkanen, L. P. Karjalainen, and D. A. Porter: Mater. Sci. Eng. A, 2016, vol. 654, pp. 151–60.

    Article  Google Scholar 

  11. V. Kesti, A. Kaijalainen, J. Mourujärvi, and R. Ruoppa: in 13th Nord. Steel Constr. Conf. (2015).

  12. J. Hannula, D. A. Porter, M. C. Somani, A. Kaijalainen, P. Suikkanen, Y. R. Yang, and S. Tsai: in Int. Symp. Wear Resist. Alloy. Min. Process. Ind. (ASM, Sao Paulo, 2015), p. to be published.

  13. R. Barbosa, F. Boratto, S. Yue, and J. J. Jonas: in Processing Microstructure and Properties of HSLA Steels, edited by A. J. Deardo, TMS, Warrendale, 1988, pp. 51–61.

    Google Scholar 

  14. F. C. Campbell: Elements of Metallurgy and Engineering Alloys, ASM International, Materials Park, Ohio, 2008.

    Google Scholar 

  15. W. Steven and A. G. Haynes: J. Iron Steel Inst., 1956, vol. 183, pp. 349–59.

    Google Scholar 

  16. W. Stuhlmann: Härterei Tech. Mitteilungen, 1954, vol. 6, pp. 31–48.

    Google Scholar 

  17. A. Brownrigg, P. Curcio, and R. Boelen: Metallography, 1975, vol. 8, pp. 529–33.

    Article  Google Scholar 

  18. R. L. Higginson and C. M. Sellars: Worked Examples in Quantitative Metallography, Maney, London, 2003.

    Google Scholar 

  19. G. Krauss: SteelsProcessing, Structure, and Performance, 2nd ed., ASM International, Materials Park, 2015.

    Google Scholar 

  20. B. Bacroix: Effect of Molybdenum on Dynamic Precipitation and Recrystallization in Niobium and Vanadium Bearing Steels, McGill University, 1982.

  21. I. Kozasu: in Int. Conf. Thermomechanical Process. Steels Other Mater., T. Chandra and T. Sakai, eds., The Minerals, Metals & Materials Society, Wollongong, 1997, pp. 47–55.

  22. F.B. Pickering: in Microalloying’75, edited by M. Korchysky (Union Carbide Corporation, Washinghton DC, 1977), pp. 9–31.

  23. G.D. Wang, Z.D. Wang, J.B. Qu, Z.Y. Jiang, and X.H. Liu: in Int. Conf. Thermomechanical Process. Steels Other Mater., T. Chandra and T. Sakai, eds., The Minerals, Metals & Materials Society, Wollongong, 1997, pp. 717–23.

  24. K.A. Taylor and S.S. Hansen: in Heat Treat. Surf. Eng. New Technol. Pract. Appl., Chicago, 1988, pp. 137–42.

  25. M.C. Somani, D.A. Porter, J.M. Pyykkönen, J.M. Tarkka, J.I. Kömi, T. A. Intonen, and L.P. Karjalainen: in Int. Conf. Microalloyed Steels Process. Microstruct. Prop. Perform., Association for Iron & Steel Technology, Pittsburgh, 2007, pp. 95–106.

  26. J. Pyykkönen, P. Suikkanen, M. C. Somani, and D. A. Porter: Matériaux Tech., 2012, vol. 100, pp. S17–19.

    Google Scholar 

  27. H.K. D.H. Bhadeshia, Bainite in Steels: Transformations, Microstructure and Properties, 2nd ed., Institute of Materials, London, 2001.

  28. N. J. Wittridge and J. J. Jonas: Acta Mater., 2000, vol. 48, pp. 2737–49.

    Article  Google Scholar 

  29. C. G. Kang, H. G. Kang, H. C. Kim, M. Y. Huh, and H. G. Suk: J. Mater. Process. Technol., 2007, vol. 187–188, pp. 542–45.

    Article  Google Scholar 

  30. M. Oka and T. Takechi: in Formability Metall. Struct., A. Sachdev and J. D. Embury, eds., Metallurgical Society, Warrendale, 1986, pp. 83–99.

  31. K. Yamazaki, M. Oka, H. Yasuda, Y. Mizuyama, and H. Tsuchiya, Nippon Steel Tech. Rep., 1995, vol. 64, pp. 37–44.

    Google Scholar 

  32. E. Schmid and W. Boas: Kristallplastizität: Mit Besonderer Berücksichtigung Der Metalle (in German), Springer, Berlin, 1935.

    Book  Google Scholar 

  33. W. F. Hosford: Mechanical Behavior of Materials, Cambridge University Press, New York, 2005.

    Book  Google Scholar 

  34. R. J. Asaro: Acta Metall., 1979, vol. 27, pp. 445–53.

    Article  Google Scholar 

  35. C. N. Reid: Deformation Geometry for Materials Scientists, Pergamon Press, Oxford, 1973.

    Google Scholar 

  36. I. L. Dillamore, J. G. Roberts, and A. C. Bush: Met. Sci., 1979, vol. 13, pp. 73–77.

    Article  Google Scholar 

  37. S. Zajac, V. Schwinn, and K. H. Tacke: Mater. Sci. Forum, 2005, vol. 500–501, pp. 387–94.

    Article  Google Scholar 

  38. T. Furuhara, H. Kawata, S. Morito, G. Miyamoto, and T. Maki: Metall. Mater. Trans. A Phys. Metall. Mater. Sci., 2008, vol. 39 A, pp. 1003–13.

  39. R. K. Ray and J. J. Jonas: Int. Mater. Rev., 1900, vol. 35, pp. 1–36.

    Article  Google Scholar 

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Acknowledgments

The financial support of the Finnish Funding Agency for Technology and Innovation (Tekes) in the Breakthrough Steels and Applications Program of the Finnish Metals and Engineering Competence Cluster (FIMECC Ltd.) is gratefully acknowledged. The authors would like to thank Mr. Juha Uusitalo for the help during the experiments.

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Correspondence to Antti Juhani Kaijalainen.

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Manuscript submitted January 1, 2016.

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Kaijalainen, A.J., Liimatainen, M., Kesti, V. et al. Influence of Composition and Hot Rolling on the Subsurface Microstructure and Bendability of Ultrahigh-Strength Strip. Metall Mater Trans A 47, 4175–4188 (2016). https://doi.org/10.1007/s11661-016-3574-8

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