A ND-FE-O INTERGRANULAR PHASE IN ND-FE-B SINTERED MAGNETS AND ITS EFFECT ON COERCIVITY

被引：8
作者：
CHEN, ZM
WANG, NX
SONG, XP
WANG, XT
机构：
[1] Department of Materials Science and Engineering, Xi’ an Jiaotong University, Xi’ an, 710049, P. R.
来源：
IEEE TRANSACTIONS ON MAGNETICS | 1995年 / 31卷 / 03期
基金：
中国国家自然科学基金; 中国博士后科学基金;
关键词：
D O I：
10.1109/20.376242
中图分类号：
TM [电工技术]; TN [电子技术、通信技术];
学科分类号：
0808 ; 0809 ;
摘要：
The intergranular microstructure and coercivity of Nd richer NdxFe93-xB7 (x = 16-28) sintered magnets have been systematically studied by means of scanning electron microscopy, analytical transmission electron microscopy, scanning auger multiprobe, thermomagnetic analysis, magnetic measurement and annealing experiments. A new stable Nd-Fe-O ferromagnetic phase with a composition NdFe2Ox (x almost-equal-to 0.3) and a Curie temperature of 145-degrees-C is found in the intergranular regions of the magnets, due to the introduction of a considerable amount of oxygen during magnet processing and its segregation in the intergranular regions. The phase forms at approximately 650-degrees-C and its volume fraction reaches a maximum of approximately 4% in the Nd22Fe71B7 magnets. This new phase has a strong hindrance effect on the propagation of reversed domain walls between Nd2Fe14B grains, and thus leads to a considerable enhancement of coercivity. Raising the Curie temperature of this phase would be a new important approach to improve the high-temperature oercivity of Nd-Fe-B magnets.
引用
收藏
页码：2215 / 2219
页数：5
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