Abstract
Size effect in Fe-Ni-alloy nanoclusters has been studied by the molecular-dynamics (MD) method using multiparticle interatomic interaction potentials. It is shown that the α-γ transformation in nanoparticles with sizes d>3.5 nm proceeds by the mechanism of nucleation at grain boundaries and propagation of fcc-phase plates. As a result of the transformation, a twinned lamellar domain structure is formed. In particles with sizes 3.0<d<3.5 nm, the α-γ transformation is accompanied by radial-symmetry atomic movements that are close to those characteristic of the Bain scheme. This results in the formation of a single-domain fcc phase. In nanoparticles with sizes 1.5<d<3.0 nm, the α-γ transformation proceeds via an intermediate state that is retained within a temperature range of a few hundreds of kelvins and is characterized by an incomplete phase transformation. It has been found that in Fe-Ni clusters with sizes d≤1.5 nm, the α-γ transformation does not occur. During heating, the initial bcc configuration turns into an icosahedral one through polytetrahedral or amorphous-like configuration.
Similar content being viewed by others
References
R. A. Andrievskii and A. M. Glezer, “Size Effects in Nanocrystalline Materials: II. Mechanical and Physical Properties,” Fiz. Met. Metalloved. 89(1), 91–112 (2000) [Phys. Met. Metallogr. 89, 83–102 (2000)].
E. N. Blinova, A. M. Glezer, N. B. D’yakonova, and V. A. Zhorin, “Size Effect upon Martensitic Transformations in Melt-Quenched Iron-Nickel Alloys,” Izv. Ross. Akad. Nauk, Ser. Fiz. 65(10), 144–1449 (2001).
V.A. Lobodyuk, “Size Effect upon Martenistic Transformations,” Fiz. Met. Metalloved. 99(2), 29–40 (2005) [Phys. Met. Metallogr. 99, 143–153 (2005)].
V. G. Pushin, N. I. Kourov, T. E. Kuntsevich, et al., “Nanocrystalline TiNi-Based Shape-Memory Materials Produced by Ultrarapid Quenching from Melt,” Phys. Met. Metallogr. 94(Suppl. 1), S107–S118 (2002).
V. G. Pushin and R. Z. Valiev, “Regularities of Phase and Structural Transformations, Physical Properties, and Applications of TiNi-Based Alloys: Achievements and Prospects,” in Abstracts of the Conference on Phase Transformations and Strength of Crystals, Chernogolovka, 2004 (Chemogolovka, 2005), p. 134.
K. Kadau, P. Entel, T. C. Germann, et al., “Large-Scale Molecular-Dynamics Study of the Nucleation Process of Martensite in Fe-Ni Alloys,” J. Phys. IV 11(Pr8), 17–22 (2001).
R. Meyer and P. Entel, “Martensite-Austenite Transition and Phonon Dispersion Curves of Fe100−x Nix Studied by Molecular-Dynamics Simulations,” Phys. Rev. B: Condens. Matter Mater. Phys. 57(9), 5140–5147 (1998).
P. Entel, R. Meyer, K. Kadau, et al., “Martensitic Transformations: First-Principles Calculations Combined with Molecular-Dynamics Simulations,” Eur. Phys. J. B 5, 379–388 (1998).
J. Neuhaus, W. Petry, and A. Krimmel, Phonon Softening and Martensitic Transformation in α-Fe, Physica B 234–236, 897–899 (1997).
P. Entel, R. Meyer, and K. Kadau, “Molecular Dynamics Simulations of Martensitic Transitions,” Philos. Mag. B 80(2), 183–194 (2000).
K. Kadau, P. Entel, and P. S. Lomdahl, “Molecular-Dynamics Study of Martensitic Transformations in Sintered Fe-Ni Nanoparticles,” Comput. Phys. Commun. 147, 126–129 (2002).
Yu. N. Gornostyrev, I. N. Kar’kin, et al., “Evolution of the Atomic Structure of Metal Clusters upon Heating and Cooling. Computer Simulation of FCC Metals,” Fiz. Met. Metalloved. 96(2), 19–26 (2003) [Phys. Met. Metallogr. 96, 135–144 (2003)].
P. Entel, W. A. Adeagbo, M. Sugihara, et al., “Molecular Dynamics Simulations in Biology, Chemistry and Physics,” Lect. Notes. Phys. 642, 177–207 (2004).
S. Sugano and H. Koizumi, Microcluster Physics (Springer, Berlin, 1998), pp. 236–370.
C. L. Cleveland, W. D. Luedtke, and V. Landman, “Melting of Gold Clusters: Icosahedral Precursors,” Phys. Rev. Lett. 81, 2036–2040 (1998).
Author information
Authors and Affiliations
Additional information
Original Russian Text © L. E. Kar’kina, I.N. Kar’kin, Yu.N. Gornostyrev, 2006, published in Fizika Metallov i Metallovedenie, 2006, Vol. 101, No. 2, pp. 146–157.
Rights and permissions
About this article
Cite this article
Kar’kina, L.E., Kar’kin, I.N. & Gornostyrev, Y.N. Structural transformations in Fe-Ni-alloy nanoclusters: Results of molecular-dynamic-simulation. Phys. Metals Metallogr. 101, 130–140 (2006). https://doi.org/10.1134/S0031918X06020062
Received:
Issue Date:
DOI: https://doi.org/10.1134/S0031918X06020062