Effects of Nd-rich phase on the improved properties and recoil loops for hot deformed Nd-Fe-B magnets
Effects of Nd-rich phase on the improved properties and recoil loops for hot deformed Nd-Fe-B magnets
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DOI：
10.1016/j.actamat.2016.06.015
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发表时间：
2016-08
期刊：
影响因子：
9.4
通讯作者：
Y. Hou;Y. Wang;Y. Huang;S. Li;S. Ma;Zhong W. Liu;D. Zeng;L. Zhao;Z. Zhong
中科院分区：
文献类型：
--
作者：
Y. Hou;Y. Wang;Y. Huang;S. Li;S. Ma;Zhong W. Liu;D. Zeng;L. Zhao;Z. Zhong
富 Nd 相在润湿晶界和促进热变形 (HD) Nd-Fe-B 磁体织构形成方面发挥着关键作用。在这项研究中，在纳米晶 HD 磁体中观察到尺寸高达几微米的富 Nd 相的不均匀分布。富Nd相的聚集被证实是由放电等离子体烧结（SPS）制备的低密度前驱体引起的。富 Nd 相聚集引起的大局部退磁场导致开式反冲环并降低矫顽力。通过消除富 Nd 相聚集来减少反冲环开放度后，HD 磁体的矫顽力从 226 kA/m 显着提高到 995 kA/m，并获得了 293 kJ/m3 的高最大磁能积。微观结构和矫顽力对反冲环特性的依赖性提出了改善纳米晶 HD Nd-Fe-B 磁体磁性能的重要方法。
Nd-rich phase plays a critical role in wetting grain boundary and facilitating texture formation for hot deformed (HD) Nd-Fe-B magnets. In this study, a non-uniform distribution of Nd-rich phase with dimension up to a few micrometers was observed in nanocrystalline HD magnets. The aggregation of the Nd-rich phase is confirmed to result from the low density precursor prepared by spark plasma sintering (SPS). The large local demagnetizing fields induced by Nd-rich phase aggregation led to the open recoil loops and reduced coercivity. Upon reducing recoil loop openness by eliminating Nd-rich phase aggregation, the coercivity of the HD magnet was significantly improved from 226 kA/m to 995 kA/m, and a high maximum energy product of 293 kJ/m3was obtained. The dependences of microstructure and coercivity on the recoil loop characteristics suggest an essential approach for improving the magnetic properties of nanocrystalline HD Nd-Fe-B magnets.