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arXiv · 1703.03684

Micromagnetic Simulations for Coercivity Improvement through Nano-Structuring of Rare-Earth Free L1$_0$-FeNi Magnets

Alexander Kovacs·Johann Fischbacher·Harald Oezelt·Thomas Schrefl·Andreas Kaidatzis·Ruslan Salikhov·Michael Farle·George Giannopoulos·Dimitris Niarchos
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Abstract

In this work we investigate the potential of tetragonal L1$_0$ ordered FeNi as candidate phase for rare earth free permanent magnets taking into account anisotropy values from recently synthesized, partially ordered FeNi thin films. In particular, we estimate the maximum energy product ($BH$)$_\mathrm{max}$ of L1$_0$-FeNi nanostructures using micromagnetic simulations. The maximum energy product is limited due to the small coercive field of partially ordered L1$_0$-FeNi. Nano-structured magnets consisting of 128 equi-axed, platelet-like and columnar-shaped grains show a theoretical maximum energy product of 228 kJ/m$^3$, 208 kJ/m$^3$, 252 kJ/m$^3$, respectively.

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BibTeXRIS

Alexander Kovacs, Johann Fischbacher, Harald Oezelt, Thomas Schrefl, Andreas Kaidatzis, Ruslan Salikhov, Michael Farle, George Giannopoulos, Dimitris Niarchos. 2017-05-07. Micromagnetic Simulations for Coercivity Improvement through Nano-Structuring of Rare-Earth Free L1$_0$-FeNi Magnets. https://doi.org/10.1109/tmag.2017.2701418

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