Structural phase transformation mechanism of α-Fe under tensile loading at high strain rate: molecular dynamics study

Document Type : Original Article

Authors

1 Department of Physics, University of Tehran

2 Faculty of Mechanical Engineering, Shahid Rajaee Teacher Training University

3 Department of Physics, Shahid Rajaee Teacher Training University

Abstract
One of the most significant properties of metals is their ability to undergo phase transformations and structural changes in response to external forces, temperature variations, and other environmental factors. In this study, molecular dynamics (MD) simulations are employed to investigate phase transformation mechanisms and deformation behavior in a pristine and defect-free α-Fe specimen subjected to high strain rate tensile loading. The results reveal that, during the loading process, the microstructural transformation initiates from a body-centered cubic (bcc) structure to a face-centered cubic (fcc) structure, followed by a subsequent transition from fcc to a hexagonal close-packed (hcp) configuration. Furthermore, the critical stress levels follow the order  stress(hcp)>stress(fcc)>stress(unknown)>stress(bcc), indicating that the hcp structure requires the highest stress to initiate transformation. Consequently, bond rupture and fracture nucleation are most likely to occur in the vicinity of this phase.

Keywords

Subjects

  1. W A Bassett and E Huang, Science 238 (1987) 780.
  2. J C Boettger and D C Wallace, Rev. B 55 (1997) 2840.
  3. K Yano and Y Horie, J. Plast. 18 (2002) 1427.
  4. K J Caspersen, et al., Rev. Lett. 93 (2004) 115501.
  5. B J Jensen, G T Gray III, and R S Hixson, Appl. Phys. 105 (2009) 103502.
  6. N Gunkelmann, et al., Rev. B 86 (2012) 144111.
  7. K Wang, et al., J. Plast. 59 (2014) 180.
  8. K Wang, et al., J. Plast. 96 (2017) 56.
  9. W F Smith and J Hashemi, “Foundations of Materials Science and Engineering”, McGraw-Hill (2006).
  10. HKDH Bhadeshia and RWK Honeycombe, “Steels: Microstructure and Properties”, Butterworth-Heinemann (2006).
  11. D A Porter, K E Easterling, and M Y M Sherif, “Phase Transformations in Metals and Alloys”, CRC Press (2009).
  12. J Song and W Curtin, Mater. 12 (2013) 145.
  13. H Y Song, L Zhang, and M X Xiao, Lett. A 380 (2016) 917.
  14. M W Finnis and J E Sinclair, Mag. A 50 (1984) 45.
  15. M I Mendelev, et al., Mag. 83 (2003) 3977.
  16. S J Wang, et al., Rep. 3 (2013) 1086.
  17. K Kadau, et al., Science 296 (2002) 1681.
  18. K Kadau, et al., Rev. Lett. 98 (2007) 135701.
  19. J L Shao, et al., Phys. Condens. Matter 21 (2009) 245703.
  20. F F Abraham, et al., Natl. Acad. Sci. U.S.A. 99(9) (2002) 5783.
  21. Y Mishin and M J Mehl, Rev. B 63 (2001) 12.
  22. S Plimpton, Comput. Phys. 117 (1995) 1.
  23. WC Swope, et al., Chem. Phys. 76 (1982) 637.
  24. G Yuan, Z Wei, and G Li, Comput. Appl. Math 255 (2014) 86.
  25. Nosé, J. Chem. Phys. 81 (1984) 511.
  26. W G Hoover, Rev. A 31 (1985) 1695.
  27. M Parrinello and A Rahman, Appl. Phys. 52 (1981) 7182.
  28. N Metropolis, et al., Chem. Phys. 21 (1953) 1087.
  29. D Faken and H Jonsson, Mater. Sci. 2(2) (1994) 279.
  30. A Stukowski, Simul. Mater. Sci. Eng. 18 (2010) 015012.
  31. J L Shao, et al., Rep. 8 (2018) 7650.

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