Microstructure, properties and strengthening mechanisms of low-carbon steel subjected to equal-channel angular pressing

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Abstract

In the work, an ultrafine-grained (UFG) state was formed in a low-carbon steel by equal-channel angular pressing (ECAP) (8 passes, 200 °С), demonstrating high mechanical properties (yield strength is 1021 MPa, tensile strength is 1072 MPa, ductility is 10.7 %) along with satisfactory corrosion resistance (0.345 mm/year). To explain the reasons for improvement of strength properties and changes in corrosion properties, UFG steel microstructure was analysed using electron microscopy and X-ray scattering methods. Specifically, electron microscopy methods revealed structural refinement of ECAP-processed steel, resulting in the formation of equiaxed grains averaged ~240 nm in size. Modified Williamson–Hall and Warren–Averbach X-ray procedures were applied to find the patterns of changes in coherent scattering domains size, density ρ and fraction fs of screw-type dislocations, effective outer cut-off radius Re of dislocations and some other parameters of low-carbon steel depending on a number of ECAP passes (degree of deformation). X-ray diffraction analysis and small-angle X-ray scattering methods were used to determine evolution trends of mass fraction, size and morphology of various precipitates depending on the number of ECAP passes. Based on the obtained data, a model of microstructure transformation during UFG state formation in steel was proposed. Furthermore, strengthening mechanisms of both coarse-grained and UFG steels were discussed. It was found that in initial state, steel strength was primarily ensured by grain-boundary strengthening and precipitation of small Ме23С6 and Ме3С2 precipitates. It was shown that during UFG structure formation, steel strength increases due to grain-boundary strengthening and dislocation density increase. The contribution of precipitates in the UFG state to the strengthening decreases and this is due to their growth during ECAP processing. It was found that an increase in corrosion rate of UFG steel results from a decrease in ferrite grain size, an increase in grain-boundary dislocations density and a cellular structure formation.

About the authors

Andrey V. Malinin

LLC RN-BashNIPIneft

Author for correspondence.
Email: MalininAV@bnipi.rosneft.ru
ORCID iD: 0000-0003-1185-5648

PhD (Engineering), Deputy General Director for Research

Россия, 450006, Russia, Ufa, Lenin Street, 86/1

References

  1. Zayed E.M., Shazly M., El-Sabbagh A., El-Mahallawy N.A. Deformation behavior and properties of severe plastic deformation techniques for bulk materials: A review. Heliyon, 2023, vol. 9, no. 6, article number e16700. doi: 10.1016/j.heliyon.2023.e16700.
  2. Enikeev N.A., Abramova M.M., Smirnov I.V., Mavlyutov A.M., Kim J.G., Lee C.S., Kim H.S. Performance of twinning-induced plasticity steel processed by multipass equal channel angular pressing at high temperatures. Physical mesomechanics, 2024, vol. 27, no. 6, pp. 698–709. doi: 10.1134/S1029959924060079.
  3. Figueiredo R.B., Langdon T.G. Deformation mechanisms in ultrafine-grained metals with an emphasis on the Hall–Petch relationship and strain rate sensitivity. Journal of Materials Research and Technology, 2021, vol. 14, pp. 137–159. doi: 10.1016/j.jmrt.2021.06.016.
  4. Kasaeian-Naeini M., Sedighi M., Hashemi R. Severe plastic deformation (SPD) of biodegradable magnesium alloys and composites: A review of developments and prospects. Journal of Magnesium and Alloys, 2022, vol. 10, no. 4, pp. 938–955. doi: 10.1016/j.jma.2021.11.006.
  5. Li Changsheng, Shao Zhibao, Li Kun, Peng Lianggui, Dong Jingbo. Mechanical properties and plastic deformation mechanisms of Fe–Cr–Ni–Mn–Mo–0.37/0.47 N low magnetic stainless-steel plates. Materials Chemistry and Physics, 2025, vol. 344, article number 131114. doi: 10.1016/j.matchemphys.2025.131114.
  6. Levitas V.I. Steady states in severe plastic deformations and microstructure at normal and high pressure. Journal of Materials Research and Technology, 2025, vol. 36, pp. 382–397. doi: 10.1016/j.jmrt.2025.03.060.
  7. Ranaware P.G. Effect of severe plastic deformation on aging kinetics of precipitation hardening 17–4 stainless steel. Materials Today: Proceedings, 2022, vol. 62, part 14, pp. 7600–7604. doi: 10.1016/j.matpr.2022.04.783.
  8. Usmanov E.I., Rezyapova L.R., Valiev R.Z. High-strength state and strengthening mechanisms of ultrafine-grained titanium. Physical Mesomechanics, 2023, vol. 26, no. 5, pp. 483–494. doi: 10.1134/s1029959923050016.
  9. Cho Yeonggeun, Cho Hyung-Jun, Noh Han-Seop, Kim Sung-Ho, Kim Sung-Joon. Strengthening mechanism and martensite transformation behavior in grain-refined low-Ni austenitic stainless steel. Materials Science and Engineering: A, 2024, vol. 916, article number 147368. doi: 10.1016/j.msea.2024.147368.
  10. Mohd Yusuf Sh., Chen Ying, Yang Shoufeng, Gao Nong. Microstructural evolution and strengthening of selective laser melted 316L stainless steel processed by high-pressure torsion. Materials Characterization, 2019, vol. 159, article number 110012. doi: 10.1016/j.matchar.2019.110012.
  11. Zrník J., Kraus L., Dobatkin S.V. Influence of Thermal Condition of ECAP on Microstructure Evolution in Low Carbon Steel. Materials Science Forum, 2007, vol. 558-559, part 1, pp. 611–616. doi: 10.4028/0-87849-443-x.611.
  12. Zrnik J., Lapovok R., Raab G.I. Prior thermo-mechanical processing to modify structure and properties of severely deformed low carbon steel. IOP Conference Series: Materials Science and Engineering, 2014, vol. 63, article number 012066. doi: 10.1088/1757-899X/63/1/012066.
  13. Wang Jing Tao, Xu Cheng, Du Zhong Ze, Qu Guo Zhong, Langdon T.G. Microstructure and properties of a low-carbon steel processed by equal-channel angular pressing. Materials Science and Engineering: A, 2005, vol. 410–411, pp. 312–315 doi: 10.1016/j.msea.2005.08.111.
  14. Hajizadeh K., Kurzydlowski K.J. On the possibility of fabricating fully austenitic sub-micron grained AISI 304 stainless steel via equal channel angular pressing. Material Today Communications, 2023, vol. 35, article number 105641. doi: 10.1016/j.mtcomm.2023.105641.
  15. Wauthier-Monnin A., Chauveau T., Castelnau O., Réglé H., Bacroix B. The evolution with strain of the stored energy in different texture components of cold-rolled IF steel revealed by high resolution X-ray diffraction. Materials Characterization, 2015, vol. 104, pp. 31–41. doi: 10.1016/j.matchar.2015.04.005.
  16. Hao Ting, Tang Haiyin, Luo Guangnan, Wang Xianping, Liu Changsong, Fang Qianfeng. Enhancement effect of inter-pass annealing during equal channel angular pressing on grain refinement and ductility of 9Cr1Mo steel. Materials Science and Engineering: A, 2016, vol. 667, pp. 454–458. doi: 10.1016/j.msea.2016.04.098.
  17. Das Bakshi S., Sinha D., Ghosh Chowdhury S. Anisotropic broadening of XRD peaks of α′-Fe: Williamson–Hall and Warren–Averbach analysis using full width at half maximum (FWHM) and integral breadth (IB). Materials Characterization, 2018, vol. 142, pp. 144–153. doi: 10.1016/j.matchar.2018.05.018.
  18. Das S.R., Shyamal S., Shee S.K., Kömi J.I., Sahu P. X-ray line profile analysis of the deformation microstructure in a medium-grained Fe-Mn-Al-C austenitic steel. Materials Characterization, 2021, vol. 172, article number 110833. doi: 10.1016/j.matchar.2020.110833.
  19. Schafler E., Zehetbauer M.J., Ungár T. Measurement of screw and edge dislocation density by means of X-ray Bragg profile analysis. Materials Science and Engineering: A, 2001, vol. 319-321, pp. 220–223. doi: 10.1016/S0921-5093(01)00979-0.
  20. Sitdikov V.D., Murashkin M.Yu., Valiev R.Z. Full-scale use of X-ray scattering techniques to characterize aged Al-2wt.%Cu alloy. Journal of Alloys and Compounds, 2018, vol. 735, pp. 1792–1798. doi: 10.1016/j.jallcom.2017.11.282.
  21. Gubicza J., Ungár T. Characterization of defect structures in nanocrystalline materials by X-ray line profile analysis. Zeitschrift für Kristallographie - Crystalline Materials, 2007, vol. 222, no. 11, pp. 567–579. doi: 10.1524/zkri.2007.222.11.567.
  22. Ungár T., Dragomir I., Révész Á., Borbély A. The contrast factors of dislocations in cubic crystals: the dislocation model of strain anisotropy in practice. Journal of Applied Crystallography, 1999, vol. 32, pp. 992–1002. doi: 10.1107/s0021889899009334.
  23. Park Soon-Dong, Kim Sung Youb, Kim Daeyong. Ab initio investigations of the interfacial bond of Fe(001)/Al(001). Materials Today Communications, 2021, vol. 26, article number 102107. doi: 10.1016/j.mtcomm.2021.102107.
  24. Ren Yang, Zuo Xiaoding. Synchrotron X-Ray and Neutron Diffraction, Total Scattering, and Small-Angle Scattering Techniques for Rechargeable Battery Research. Small Methods, 2018, vol. 2, no. 8, article number 1800064. doi: 10.1002/smtd.201800064.
  25. Huyan F., Larker R., Rubin P., Hedström P. Effect of Solute Silicon on the Lattice Parameter of Ferrite in Ductile Irons. ISIJ International, 2014, vol. 54, no. 1, pp. 248–250. doi: 10.2355/isijinternational.54.248.
  26. Mughrabi H. Dislocation wall and cell structures and long-range internal stresses in deformed metal crystals. Acta Metallurgica, 1983, vol. 31, no. 9, pp. 1367–1379. doi: 10.1016/0001-6160(83)90007-x.
  27. Zehetbauer M. Cold work hardening in stages IV and V of F.C.C. metals – II. Model fits and physical results. Acta Metallurgica et Materialia, 1993, vol. 41, no. 2, pp. 589–599. doi: 10.1016/0956-7151(93)90089-b.
  28. Ungár T., Révész Á., Borbély A. Dislocations and Grain Size in Electrodeposited Nanocrystalline Ni Determined by the Modified Williamson–Hall and Warren–Averbach Procedures. Journal of Applied Crystallography, 1998, vol. 31, pp. 554–558. doi: 10.1107/S0021889897019559.
  29. Wu R., Zaiser M. Cell structure formation in a two-dimensional density-based dislocation dynamics model. Journal of Materials Science: Materials Theory, 2021, vol. 5, article number 3. doi: 10.1186/s41313-020-00025-x.
  30. Sauvage X., Enikeev N.A., Valiev R.Z., Nasedkina Y., Murashkin M.Yu. Atomic-scale analysis of the segregation and precipitation mechanisms in a severely deformed Al–Mg alloy. Acta Materialia, 2014, vol. 72, pp. 125–136. doi: 10.1016/j.actamat.2014.03.033.
  31. Islamgaliev R.K., Nikitina M.A., Ganeev A.V., Sitdikov V.D. Strengthening mechanisms in ultrafine-grained ferritic/martensitic steel produced by equal channel angular pressing. Materials Science and Engineering: A, 2019, vol. 744, pp. 163–170. doi: 10.1016/j.msea.2018.11.141.

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