摘要
研究烧结Nd_Fe_B磁体的低磁时效问题.实验显示样品在室温293和353K经920d磁时效后,磁通量的衰减率分别为1.4%和13%,经老化处理后,磁通量的衰减率分别为6‰和6.9%,说明未做老化处理的磁体时间稳定性较差.假设微观杂质运动临界能E1、极微小杂质运动临界能E2和移动原子对键取向转动临界能E3对时间稳定性的影响最为显著,依据半经典的Boltzmann统计分布,导出的烧结Nd_Fe_B磁体的低磁时效所满足的规律.理论结果与实验相符.
The irreversible flux loss （FL） of sintered Nd-Fe-B magnets has been investigated after aging for about 920 d. Exposed at room temperature （RT） and 353 K, the values of FL are about 1.4% and 13%, respectively. However, with a pre-aging the FL are about 6‰ and 6.9% for the magnets exposed at RT and 353 K, respectively. Therefore, the stability of flux has been improved obviously by the pre-aging. A phenomenological formula, based on the Bohzmann statistics, has been used to discuss the effect of microstructure on FL. It is found that the experimental results can be well explained by the formula.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第12期5895-5900,共6页
Acta Physica Sinica
基金
国家高技术研究发展计划(批准号:2003AA32G020
2004AA32G083)资助的课题.~~
