Stacking Fault Energy and Microstructural Insight into the Dynamic Deformation of High-Manganese TRIP and TWIP Steels

Document Type : Research Paper

Authors

1 Department of Materials Science and Engineering, College of Chemical and Metallurgical Engineering, Shiraz Branch, Islamic Azad University, Shiraz 71955, Iran

2 Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz 71348, Iran

Abstract

The dynamic behavior of three high manganese steels with very different stacking fault
energy (SFE) values (4-30 mJ/m2) were studied using high strain rate torsional tests. The hotrolled
microstructure of the steel with the lowest SFE of 4 mJ/m2 consisted of a duplex mixture of
austenite and ε-martensite, but those of the other two steels were fully austenitic. The deformed
microstructures were studied by optical and electron microscopy. The quasi-static deformation of
the low-SFE steel was accompanied with profuse martensitic transformation. However, when this
steel was deformed at high strain rates (> 500 /s), martensite formation was reduced due to the
adiabatic temperature rise and the increased SFE of the steel. The deformation of the steel with
moderate SFE of 18 mJ/m2 at all the tested strain rates was mainly controlled by the formation of
mechanical twins that was leading to an excellent ductility of about 55% even at the highest strain
rate of ~1700 /s. In contrast, dynamic deformation of the steel with the highest SFE of 30 mJ/m2
led to the appearance of some shear bands. This was ascribed to the decreased twinning and work
hardening rate in this steel. Finally, the topographic studies showed that the fracture surface of the
low-SFE steel contained relatively larger cleavage areas and smaller dimples suggesting a
relatively more brittle fracture. This was related to the presence of brittle ε and α` martensite
phases in this steel.

Keywords

References

[1] V. J. Slycken, P. Verleysen, J. Degrieck, J. Bouquerel and B. C. De Cooman, Dynamic response of aluminum
containing TRIP steel and its constituent phases, Material Science and Engineering A, 460–461 (2007) 516–524.
[2] Z. H. Cai, H. Ding, X. Xue and Q. B. Xin, Microstructural evolution and mechanical properties of hot-rolled
11% manganese TRIP steel, Materials Science & Engineering A, 560 (2013) 388-395.
[3] L. A. Dobrzanski and W. Borek, Thermo-mechanical treatment of Fe–Mn–(Al,Si) TRIP/TWIP steels, Archives
of Civil and Mechanical Engineering, (2012) 299-304.
[4] S. Allain, J. P. Chateau, O. Bouaziz, S. Migot and N. Guelton, "Correlations between the calculated stacking
fault energy and the plasticity mechanisms in Fe–Mn–C alloys," Materials Science and Engineering A, Vols.
387-389, pp. 158-162, 2004.
[5] A. Dumay, J. P. Chateau, S. Allain, M. S. and O. Bouaziz, Influence of addition elements on the stacking-fault
energy and mechanical properties of an austenitic Fe–Mn–C steel, Materials Science and Engineering A, 483-
484, (2008) 184-187.
[6] H. Idrissi, K. Renard, L. Ryeland, D. Schryvers and P. J. Jacques, On the mechanism of twin formation in Fe–
Mn–C TWIP steels, Acta Materialia, 58, (2010) 2464-2476.
[7] S. Lee, S. J. Lee, S. S. Kumar, K. Lee and B. C. De Cooman, Localized deformation in multiphase, ultra-finegrained
6 Pct Mn transformation-induced plasticity steel, Metallurgical and Materials Transactions A, 42,
(2011) 3638-3651.
[8] P. J. Gibbs, E. De Moor, M. J. Merwin, B. Clausen, S. J. G. and D. K. Matlock, Austenite stability effects on
tensile behavior of manganese-enriched-austenite transformation-induced plasticity steel, Metallurgical and
Materials Transactions A, 42, (2011) 3691-3702.
[9] O. Grassel, L. Kruger, G. Frommeyer and L. W. Meyer, High strength Fe-Mn-(Al, Si) TRIP/TWIP steels
development-properties-application, International Journal of Plasticity, 16, (2000) 1391-1409.
[10]O. Matsumura, Y. Sakuma and H. Takechi, Enhancement of elongation by retained austenite in intercritical
annealed 0.4C-1.5Si-0.8Mn Steel, Transactions of the Iron and Steel Institute of Japan, 27 (1987) 570-579,
1987.
[11]O. Bouaziz, S. Allain, C. P. Scott, C. P. and D. Barbier, High manganese austenitic twinning induced plasticity
steels: A review of the microstructure properties relationships, Current Opinion in Solid State and Materials
Science, 15 (2011) 141-168.
[12]S. Curtze and V. T. Kuokkala, Dependence of tensile deformation behavior of TWIP steels on stacking fault
energy, temperature and strain rate, Acta Materialia, 58 (2010) 5129-5141.
[13] J. Jin and Y. Lee, Strain hardening behavior of a Fe–18Mn–0.6C–1.5Al TWIP steel, Materials Science and
Engineering A, 527 (2009) 157-161.
[14]Gutierrez-Urrutia and D. Raabe, Dislocation and twin substructure evolution during strain hardening of an Fe–
22 wt.% Mn–0.6 wt.% C TWIP steel observed by electron channeling contrast imaging, Acta Materialia, 59
(2011) 6449-6462.
[15] T. A. Lebedkina, M. A. Lebyodkin, J. P. Chateau, A. Jacques and S. Allain, On the mechanism of unstable
plastic flow in an austenitic FeMnC TWIP steel, Materials Science and Engineering A, 519 (2009) 147–154.
[16]Chung, K. Ahn, D. H. Yoo, K. H. Chung, M. H. Seo and S. H. Park, Formability of TWIP (twinning induced
plasticity) automotive sheets, International Journal of Plasticity, 27(2011) 52-81.
[17] X. Sun, A. Soulami, K. S. Choi, O. Guzman and W. Chen, Effects of sample geometry and loading rate on
tensile ductility of TRIP800 steel, Materials Science and Engineering A, 541 (2012) 1-7.
[18] P. Sahu, S. Curtze, A. Das, B. Mahato, K. V. T. and S. G. Chowdhury, Stability of austenite and quasi-adiabatic
heating during high strain-rate deformation of twinning-induced plasticity steels, Scripta Materialia, 62 (2010)
5-8.
[19]A. Khosravifard, M. M. Moshksar and R. Ebrahimi, High strain rate torsional testing of a high manganese steel:
Design and Simulation, Materials and Design, 52 (2013) 495-503.
[20]Khosravifard, M. M. Moshksar and R. Ebrahimi, Mechanical behavior of TWIP steel in high strain rate torsional
test, International Journal of Iron and Steel Society of Iran, 9 (2012) 15-19.
[21]Khosravifard, Influence of high strain rates on the mechanical behavior of high manganese steels, Iranian
Journal of Materials Forming, 1 (2014) 1-10.
[22]Khosravifard, A. S. Hamada, M. M. Moshksar, R. Ebrahimi, D. A. Porter and L. P. Karjalainen, High
temperature deformation behavior of two as-cast high-manganese TWIP steels, Materials Science &
Engineering A, 582 (2013) 15-21.
[23]G. Olson and M. Cohen, A general mechanism of martensitic nucleation: Part I. General concepts and the FCCHCP
transformation, Metallurgical and Materials Transactions A, 7 (1976). 1897-1904.
[24]G. Regazzoni, P. U. F. Kocks and P. S. Follansbee, Dislocation Kinetics at High Strain Rates, Acta
Metallurgica, 35 (1987) 2865-2875.
[25]R. G. Xiong, R. Y. Fu, Y. Su, Q. Li, W. X. C. and L. Li, Tensile properties of TWIP steel at high strain rate,
Journal of Iron and Steel Research, International, 16 (2009) 81-86.

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