Title :
Effects of Cu-Nb/Zr addition on magnetic properties of Fe3 B/(Nd-Dy)2Fe14B nanocomposite magnets
Author :
Hirosawa, S. ; Miyoshi, T. ; Kanekiyo, H. ; Shigemoto, Y.
Author_Institution :
Tech. Dev. Div., Sumitomo Special Metals Co. Ltd., Osaka, Japan
fDate :
7/1/2001 12:00:00 AM
Abstract :
Improving magnetocrystalline anisotropy to create materials with high coercivity by means of partial replacement of Nd with a heavy rare earth element such as Tb and Dy requires considerable refinement of grain size in order to keep the relation between intergranular exchange energy and magnetocrystalline energy unchanged. Addition of small amounts of Cu and Zr is shown to be effective to manipulate crystallization behaviors and hence structure of the Fe3B/Nd 2Fe14B-type nanocomposite permanent magnets containing heavy rare earth elements. The impact of the simultaneous addition of Cu-Zr is that improvement of magnetic properties can he achieved with a smaller amount of additives than Cu-Nb addition reported earlier. An example is Nd3.4Dy1.0Fe71.7B18.5Cr 2.4Co2.4Cu0. 4Zr0.2 with HcJ=462 kA/m, Br=0.97 T, and (BH)max=105 kJ/m3
Keywords :
boron alloys; coercive force; composite materials; crystallisation; dysprosium alloys; grain size; iron alloys; magnetic anisotropy; nanostructured materials; neodymium alloys; permanent magnets; Cu-Nb addition; Cu-Zr addition; Fe3B-(NdDy)2Fe14B; Fe3B/(Nd,Dy)2Fe14B nanocomposite permanent magnet; coercivity; crystallization; grain size; intergranular exchange energy; magnetic properties; magnetocrystalline anisotropy; magnetocrystalline energy; Anisotropic magnetoresistance; Coercive force; Iron; Magnetic anisotropy; Magnetic materials; Magnetic properties; Neodymium; Perpendicular magnetic anisotropy; Refining; Zirconium;
Journal_Title :
Magnetics, IEEE Transactions on
