Abstract
SmCo5 sintered magnets with good thermal stability are mainly used in high-temperature field. In this study, two types of SmCoz powders with different nominal z values were mixed and synthesized into SmCo5 magnets by the traditional powder metallurgy method. The magnetic properties of the SmCo5 sintered magnet are maximum energy product of (BH)max = 172.29 kJ·m−3, remanence of Br = 7.47 × 105 A·m−1 and coercivity of Hci = 2.42 T. The results show that there are three coexisting phases in the magnet, which are SmCo5 phase, Sm2Co7 phase and Sm2O3 phase. The microstructural observation indicates that the average grain size in the magnet is about 8 μm, and the high coercivity of this magnet is attributed to these fine grains. X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) results indicate that the magnet has a well-aligned (00l) orientation texture.
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This study was financially supported by the State Key Program of Natural Science Foundation of China (No. 51331003) and the International S&T Cooperation Program of China (No. 2015DFG52020).
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Zhang, DT., Zhu, RC., Yue, M. et al. Microstructure and magnetic properties of SmCo5 sintered magnets. Rare Met. 39, 1295–1299 (2020). https://doi.org/10.1007/s12598-018-01198-8
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DOI: https://doi.org/10.1007/s12598-018-01198-8