Refinement of the microstructure and enhancement of the magnetic properties in α-Fe/(Nd,Dy) 2Fe 14B nanocomposite using the two-step annealing technique
Abstract
The Nd 8-xDy xFe 87.5B 4.5 ( x=0-1.0) nanocomposites have been prepared by melt spinning and subsequent two-step heat treatment technique. The crystallization behaviors, microstructures and magnetic properties of the samples have been investigated. The experimental results show that the crystallization temperature of α-Fe soft phase has no obvious change through Dy addition while the crystallization temperature of 2:14:1 hard phase increases remarkably with increasing Dy content. By adopting a two-step heat treatment technique, a finer and more uniform microstructure can be developed. A dramatic enhancement of remanence Jr from 0.84 to 1.1 T, coercivity Hcj from 417 to 520 kA/m and energy product ( BH) m from 76.8 to 110 kJ/m 3 have been obtained in Nd 7Dy 1Fe 87.5B 4.5 (30 vol% α-Fe ) nanocomposite.
- Publication:
-
Journal of Magnetism and Magnetic Materials
- Pub Date:
- November 2006
- DOI:
- 10.1016/j.jmmm.2006.02.104
- Bibcode:
- 2006JMMM..306...51C
- Keywords:
-
- 75.50.Bb;
- 75.50.Vv;
- 75.50.Ww;
- 75.60.Gm;
- Fe and its alloys;
- High coercivity materials;
- Permanent magnets