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arXiv · 2412.14920

Inversion of Dislocation-Impurity Interactions in $\alpha$-Fe under Magnetic State Changes

Franco Moitzi·Lorenz Romaner·Andrei V. Ruban·Swarnava Ghosh·Markus Eisenbach·Oleg E. Peil
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Abstract

In this work, we investigate the dislocation-impurity interaction energies and their profiles for various \textit{3d} elements \textemdash V, Cr, Mn, Cu, Ni, and Co \textemdash in and around $1/2\langle111\rangle$ screw dislocations in $\alpha$-Fe using \textit{ab initio} methods. We consider the ferromagnetic and paramagnetic states, with the latter being modeled through both the disordered local moment model and a spin-wave approach. Our findings reveal that (1) magnetic effects are large compared to size misfit effects of substitutional impurities, and (2) dislocation-impurity interactions are dependent on the magnetic state of the matrix and thermal lattice expansion. In particular, Cu changes from core-attractive in the ferromagnetic state to repulsive in the paramagnetic state.

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Franco Moitzi, Lorenz Romaner, Andrei V. Ruban, Swarnava Ghosh, Markus Eisenbach, Oleg E. Peil. 2024-12-19. Inversion of Dislocation-Impurity Interactions in $\alpha$-Fe under Magnetic State Changes. https://arxiv.org/abs/2412.14920

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