Formation of non-ferromagnetic grain boundary phase in a Ga-doped Nd-rich Nd-Fe-B sintered magnet

SCRIPTA MATERIALIA

卷:113

Article

Sasaki, T. T.¹  Ohkubo, T.¹  Takada, Y.²  Sato, T.²  Kato, A.³  Kaneko, Y.²  Hono, K.¹ 

[1] Natl Inst Mat Sci, Ctr Magnet Mat, Elements Strategy Initiat, Tsukuba, Ibaraki 3050047, Japan

[2] Toyota Cent Res & Dev Labs Inc, Nagakute, Aichi 4801192, Japan

[3] Toyota Motor Co Ltd, Adv Mat Engn Div, Susono 4101193, Japan

关键词: Nd-Fe-B;    Sintered magnet;    Coercivity;    Ga;    Grain boundary;   

DOI  :  10.1016/j.scriptamat.2015.10.042

来源: Elsevier

【 摘 要 】

We have characterized the microstructures of as-sintered and optimally post-sinter annealed Nd-rich Ga-doped Nd-Fe-B magnets by scanning electron microscopy (SEM) and aberration-corrected scanning transmission electron microscopy (STEM). While the Nd2Fe14B grains in the as-sintered sample with a coercivity of 0.99 T are in direct contact with each other, those in the optimally annealed sample with a coercivity of 1.8 Tare completely enveloped by typically 10-nm-thick Nd-rich phase that contains little Fe. This strongly suggests that the Nd2Fe14B grains in the optimally annealed Nd-rich Ga-doped Nd-Fe-B magnets are exchange decoupled in contrast to those in the commercial sintered magnets. (C) 2015 Elsevier Ltd. All rights reserved.

【 授权许可】

Free