Abstract
The effects of Hf doping on the phase constitution and its evolution of the SmCo7−x Hf x (0 ≤ x ≤ 0.5) nanocrystalline alloys were investigated. It was found that a single TbCu7-type metastable phase can be stabilized in the nanocrystalline SmCo7−x Hf x alloys with x ≤ 0.25, and the phase decomposition occurs at higher Hf doping contents. The Hf doping plays a significant role in inhibiting grain growth at high temperatures, which is favorable for the high-temperature magnetic properties. The metastable phase is stabilized by the combined effects of nanostructuring and Hf doping. Moreover, the magnetic performance is increased due to the pinning effect and the high magnetocrystalline anisotropy of the stabilized TbCu7-type phase.
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This work was supported by the National Science Fund for Distinguished Young Scholars (51425101) and the National Natural Science Foundation of China (51371012).
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Hua, G., Song, X., Liu, D. et al. Effects of Hf on phase structure and magnetic performance of nanocrystalline SmCo7-type alloy. J Mater Sci 51, 3390–3397 (2016). https://doi.org/10.1007/s10853-015-9653-1
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DOI: https://doi.org/10.1007/s10853-015-9653-1