Lattice Instabilities and Phase Transformations in Fe from Atomistic Simulations
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The stability of the body- and face-centered cubic lattices corresponding to the α and γ phases of Fe, respectively, as well as the transformation of one phase to the other were investigated by atomistic simulations. Two interatomic potentials were used: the embedded atom method (EAM) potential of Meyer and Entel and the bond order potential (BOP) developed by Müller et al. The suitability of the potentials for investigating structural transformations in Fe was verified using nonequilibrium free energy calculations and molecular dynamics simulations. The results showed that the EAM potential is capable of describing the bcc → fcc and fcc → bcc transformations whereas no transformation was observed for the computationally more expensive BOP potential with the simulation set up used.
Keywordsfree energy calculations molecular dynamics phase transformations
R. G. A. Veiga and J. E. Guimarães Silva gratefully acknowledge funding by FAPESP Grant 2014/10294-4. M. G. Di V. Cuppari was awarded a postdoctoral fellowship at Ecole Nationale Superieure de Chimie de Lille within the action CAPES/COFECUB 770/13. The authors would like to acknowledge computing time provided on the Blue Gene/Q supercomputer supported by the Research Computing Support Group (Rice University) and Laboratório de Computação Científica Avançada (Universidade de São Paulo).
- 2.D.G. Pettifor, Bonding and Structure of Molecules and Solids, Oxford University Press, Oxford, 1995Google Scholar
- 9.S. Chiesa, P.M. Derlet, S.L. Dudarev and H. van Swygenhoven, Optimization of the Magnetic Potential for alpha-Fe, J. Phys. Condens. Matter, 2011, 23(20), art. 206001Google Scholar
- 10.R. Drautz and D.G. Pettifor, Valence-Dependent Analytic Bond-Order Potential for Transition Metals, Phys. Rev. B, 2006, 74(17), art. 174117Google Scholar
- 11.R. Drautz and D.G. Pettifor, Valence-Dependent Analytic Bond-Order Potential for Magnetic Transition Metals, Phys. Rev. B, 2011, 84(21), art. 214114Google Scholar
- 12.M. Müller, P. Erhart and K. Albe, Analytic Bond-Order Potential for bcc and fcc Iron—Comparison with Established Embedded-Atom Method Potentials, J. Phys. Condens. Matter, 2007, 19(32), art. 326220Google Scholar
- 20.R. Meyer and P. Entel, Lattice Dynamics of Martensitic Transformations Examined by Atomistic Simulations, J. Phys. IV, 1997, 7(C5), p C5-29-C5-34Google Scholar
- 22.C. Bos, J. Sietsma, and B.J. Thijsse, Molecular Dynamics Simulation of Interface Dynamics during the fcc-bcc Transformation of a Martensitic Nature, Phys. Rev. B, 2006, 73(10), art. 104117Google Scholar
- 26.H. Song and J.J. Hoyt, Barrier-Free Nucleation at Grain-Boundary Triple Junctions During Solid-State Phase Transformations, Phys. Rev. Lett., 2016, 117(23), art. 238001Google Scholar