Abstract
An investigation was conducted into the effects of annealing temperature on microstructure and tensile properties of ferritic lightweight steels. Two steels were fabricated by varying the C content, and were annealed at 573 K to 1173 K (300 °C to 900 °C) for 1 hour. According to the microstructural analysis results, κ-carbides were formed at about 973 K (700 °C), which was confirmed by equilibrium phase diagrams calculated from a THERMO-CALC program. In the steel containing low carbon content, needle-shaped κ-carbides were homogeneously dispersed in the ferrite matrix, whereas bulky band-shaped martensites were distributed in the steel containing high carbon content. In the 973 K (700 °C)-annealed specimen of the steel containing high carbon content, deformation bands were formed throughout the specimen, while fine carbides were sufficiently deformed inside the deformation bands, thereby resulting in the greatest level of strength and ductility. These results indicated that the appropriate annealing treatment of steel containing high carbon content was useful for the improvement of both strength and ductility over steel containing low carbon content.
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Notes
JEOL is a trademark of Japan Electron Optics Ltd., Tokyo.
INSTRON is a trademark of Instron, Canton, MA.
THERMO-CALC is a trademark of Thermo-Calc, Stockholm.
References
K. Sipos, L. Remy, and A. Pineau: Metall. Mater. Trans. A, 1976, vol. 7A, pp. 857–64.
L. Remy and A. Pineau: Mater. Sci. Eng., 1977, vol. A28, pp. 99–107.
O. Bouaziz and N. Guelton: Mater. Sci. Eng., 2001, vol. A319, pp. 246–49.
G. Frommeyer and U. Brüx: Steel Res. Int., 2006, vol. 77, pp. 627–33.
S.Y. Han, S.Y. Shin, S. Lee, N.J. Kim, J.H. Kwak, and K. Chin: Kor. J. Metall. Mater., 2010, vol. 48, pp. 377–86.
B.-W. Choi, D.-H. Seo, and J.-I. Jang: Metall. Mater. Int., 2009, vol. 15, pp. 373–78.
I. Choi, Y. Park, D. Son, S.-J. Kim, and M. Moon: Metall. Mater. Int., 2010, vol. 16, pp. 27–33.
Y. Kimura, K. Handa, K. Hayashi, and Y. Mishima: Intermetallics, 2004, vol. 12, pp. 607–17.
N. Ma, T. Park, D. Kim, C. Kim, and K. Chung: Metall. Mater. Int., 2010, vol. 16, pp. 427–39.
R.G. Baligidad, U. Prakash, A. Radhakrishna, V.R. Rao, P.K. Rao, and N.B. Ballal: Scripta Mater., 1997, vol. 36, pp. 667–71.
A. Radhakrishna, R.G. Baligidad, and D.S. Sarma: Scripta Mater., 2001, vol. 45, pp. 1077–82.
O. Grässel and G. Frommeyer: Mater. Sci. Technol., 1998, vol. 14, pp. 1213–16.
G. Frommeyer and J.A. Jiménezet: Metall. Mater. Trans. A, 2005, vol. 36A, pp. 295–300.
K.-H. Kim, J.-S. Lee, and D.-L. Lee: Metall. Mater. Int., 2010, vol. 16, pp. 871–76.
S.Y. Han, S.Y. Shin, S. Lee, N.J. Kim, J.H. Kwak, and K. Chin: Metall. Mater. Trans. A, 2011, vol. 42A, pp. 138–46.
B. Sundman, B. Jansson, and J.-O. Andersson: CALPHAD, 1985, vol. 9, pp. 153–90.
“TCFE2000: The Thermo-Calc Steels Database, upgraded by B.-J. Lee and B. Sundman at KTH,” KTH, Stockholm, 1999.
K.-G. Chin, H.-J. Lee, J.-H. Kwak, J.-Y. Kang, and B.-J. Lee: J. Alloys Compd., 2010, vol. 505, pp. 217–23.
R. Ayres and D.F. Stein: Acta Metall., 1971, vol. 19, pp. 789–94.
S.Y. Shin, H. Lee, S.Y. Han, C.-H. Seo, K. Choi, S. Lee, N.J. Kim, J.-H. Kwak, and K.-G Chin: Metall. Mater. Trans. A, 2010, vol. 41A, pp. 138–48.
Acknowledgments
This work was supported by POSCO under Contract No. 2008Y221. The authors thank Mr. Seok Su Sohn, POSTECH, for his help with microstructural analysis.
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Manuscript submitted January 10, 2011.
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Han, S.Y., Shin, S.Y., Lee, HJ. et al. Effects of Annealing Temperature on Microstructure and Tensile Properties in Ferritic Lightweight Steels. Metall Mater Trans A 43, 843–853 (2012). https://doi.org/10.1007/s11661-011-0942-2
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DOI: https://doi.org/10.1007/s11661-011-0942-2