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arXiv · 1302.4643

Effect of magnetism on kinetics of "gamma"-"alpha" transformation and pattern formation in iron

I. K. Razumov·Yu. N. Gornostyrev·M. I. Katsnelson
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Abstract

Kinetics of polymorphous "gamma"-"alfa" transformation in Fe is studied numerically within a model taking into account both lattice and magnetic degrees of freedom, based on first-principle calculations of the total energy for different magnetic states. It is shown that magnetoelastic phenomena, namely, a strong sensitivity of the potential relief along the Bain deformation path to the magnetic state, are crucial for the picture of the transformation. With the temperature increase, a scenario of the phase transformation evolves from a homogeneous lattice instability at T Ms. In the latter case, a stage of formation of a tweed-like structure occurs, with a strong short-range order and slow interphase fluctuations.

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I. K. Razumov, Yu. N. Gornostyrev, M. I. Katsnelson. 2013-02-27. Effect of magnetism on kinetics of "gamma"-"alpha" transformation and pattern formation in iron. https://doi.org/10.1088/0953-8984%2F25%2F13%2F135401

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