Magnetization reversal and nanostructure refinement in magnetically annealed Nd 2 Fe 14 B ∕ α - Fe -type nanocomposites

• Published in: Journal of applied physics 2005-05, Vol.97 (10), p.10F308-10F308-3
• Main Authors: Cui, B. Z., Yu, C. T., Han, K., Liu, J. P., Garmestani, H., Pechan, M. J., Schneider-Muntau, H. J.
• Format: Article
• Language: English
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.1853693

Nanostructure refinement, magnetic anisotropy and hard magnetic property enhancement have been observed in melt-spun Nd 2.4 Pr 5.6 Dy 1 Fe 84 Mo 1 B 6 nanocomposites annealed in an in-plane or out-of-plane field of 1.2 T . The magnetic annealing results in an enhancement of an out-of-plane (110) crystal texture of α - Fe and an in-plane uniaxial magnetic anisotropy of the 2:14:1 phase. Magnetic annealing also introduces finer, less angular and more homogeneously distributed soft and hard nanograins. Field dependent torque measurement indicates a complex magnetization reversal mechanism in these nanocomposites. Compared with the sample annealed without a field, there is a noticeable improvement in the hard magnetic properties for the magnetically annealed samples. Especially, the energy product ( B H ) max was enhanced by 26.6% (from 94 to 119 kJ ∕ m 3 ). The improvement in the magnetic properties is a result of the enhanced crystallographic texture, nanostructure refinement, and in-plane uniaxial magnetic anisotropy enhancement.