Computer Simulations of the Magnetic Properties of ${\rm Sm}-{\rm Co}/\alpha-{\rm Fe}$ Nanocomposite Magnets With a Core-Shell Structure

The magnetic properties of SmCo<sub>5</sub>/α-Fe nanocomposite magnets with a core-shell structure were computer-simulated for varying particle size L, α-Fe fraction, and temperature. The structure, consisting of a hard SmCo<sub>5</sub> core and a soft α-Fe shell demonstrated better magnetic properties than those of the inverse structure. The (BH)<sub>max</sub> value for anisotropic magnets was approximately 800 kJ/m<sup>3</sup> at room temperature for an L value of 6.4 nm and an α - Fe fraction of 87.5%. At 473 K, the achievable (BH)<sub>max</sub> value was approximately 700 kJ/m<sup>3</sup>. These values are comparable to and higher than those for Nd<sub>2</sub>Fe<sub>14</sub>B/α-Fe nanocomposite magnets at room temperature and 473 K, respectively, indicating a promising potential for high-temperature SmCo<sub>5</sub>/α-Fe nanocomposite magnets.

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