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arXiv · 1504.05829

Structures and magnetic properties of Co-Zr-B magnets studied by first-principles calculations

Xin Zhao·Liqin Ke·Manh Cuong Nguyen·Cai-Zhuang Wang·Kai-Ming Ho
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Abstract

The structures and magnetic properties of the Co-Zr-B alloys near the Co5Zr composition were studied using adaptive genetic algorithm and first-principles calculations to guide further experimental effort on optimizing their magnetic performances. Through extensive structural searches, we constructed the contour maps of the energetics and magnetic moments of the Co-Zr-B magnet alloys as a function of composition. We found that the Co-Zr-B system exhibits the same structural motif as the "Co11Zr2" polymorphs, which plays a key role in achieving high coercivity. Boron atoms can either substitute selective cobalt atoms or occupy the interstitial sites. First-principles calculation shows that the magnetocrystalline anisotropy energies can be significantly improved through proper boron doping.

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Xin Zhao, Liqin Ke, Manh Cuong Nguyen, Cai-Zhuang Wang, Kai-Ming Ho. 2015-04-22. Structures and magnetic properties of Co-Zr-B magnets studied by first-principles calculations. https://doi.org/10.1063/1.4922984

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