Nd2Fe14B/α-Fe纳米复合永磁材料中存在软-软、软-硬、硬-硬3种不同磁性晶粒界面.不同晶粒间的交换耦合相互作用使其有效各向异性常数Keff减小.Keff可以用这3种不同有效各向异性的统计平均值表示.计算结果显示:Keff随晶粒尺寸D的减小和软磁性成分的增加而降低.当D减小到4nm时,Keff减小为通常各向异性常数值的1/3~1/4.当软磁性相体积分数为50%时,Keff的值下降为硬磁性相对应值的1/2左右.有效各向异性与矫顽力的变化规律基本相同.
参考文献
[1] | Kneller E.F.;Hawig R. .The exchange-spring magnet: a new material principle for permanent magnets[J].IEEE Transactions on Magnetics,1991(4):3588-3560. |
[2] | Skomski R;Coey J M D .[J].Physical Review B,1993,48:15812. |
[3] | Bauer J.;Zern A.;Kronmuller H.;Seeger M. .NANOCRYSTALLINE FENDB PERMANENT MAGNETS WITH ENHANCED REMANENCE[J].Journal of Applied Physics,1996(3):1667-1673. |
[4] | Herzer G. .Grain size dependence of coercivity and permeability in nanocrystalline ferromagnets[J].IEEE Transactions on Magnetics,1990(5):1397-1402. |
[5] | Schrefl T;Fidler J;Kronmuller H .[J].Physical Review B,1994,49:6100. |
[6] | Schmidts H F;Kronmuller H .[J].Journal of Magnetism and Magnetic Materials,1994,129:361. |
[7] | Gao Y H;Zhu J H;Weng Y Q .[J].Applied Physics Letters,1999,74:1749. |
[8] | Sun X K;Zhang J;Chu Y L .[J].Applied Physics Letters,1999,74:1740. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%