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arXiv · 2409.04066

Slip-dominated structural transitions

Kanka Ghosh·Oguz Umut Salman·Sylvain Queyreau·Lev Truskinovsky
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Abstract

We use molecular dynamics to show that plastic slip is a crucial component of the transformation mechanism of a square-to-triangular structural transition. The latter is a stylized analog of many other reconstructive phase transitions. To justify our conclusions we use a novel atomistically-informed mesoscopic representation of the field of lattice distortions in molecular dynamics simulations. Our approach reveals a hidden alternating slip distribution behind the seemingly homogeneous product phase which points to the fact that lattice invariant shears play a central role in this class of phase transformations. While the underlying pattern of anti-parallel displacements may be also interpreted as microscopic shuffling, its precise crystallographic nature strongly suggests the plasticity-centered interpretation.

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Kanka Ghosh, Oguz Umut Salman, Sylvain Queyreau, Lev Truskinovsky. 2025-07-07. Slip-dominated structural transitions. https://doi.org/10.1103/x5fv-67xn

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