Title :
Bulk Nanocrystalline SmCo6.6Nb0.4 Sintered Magnet With TbCu7-Type Structure Prepared by Spark Plasma Sintering
Author :
Zhang, Dongtao ; Yue, Ming ; Zhang, Jiuxing ; Pan, Lijun
Author_Institution :
Beijing Univ. of Technol., Beijing
Abstract :
We prepared bulk nanocrystalline SmCo6.6Nb0.4 sintered magnet material by spark plasma sintering technique. X-ray diffraction patterns show that the magnet exhibits a stable TbCu7 structure. Transmission electron microscopy indicates that the microstructure of the magnet is composed of SmCo6.6Nb0.4 single-phase grains with an average grain size of 30 nm. Magnetic measurement shows that under a 7 T magnetic field, the coercivity of the magnet reaches as high as 2.8 T; the saturation magnetization and the remanence are 69.6 and 51.4 emu/g, respectively. The magnet exhibits good thermal stability with the coercivity of 0.48 T at 773 K, and the coercivity temperature coefficient beta of -0.169%/K.
Keywords :
X-ray diffraction; cobalt alloys; coercive force; grain size; magnets; nanostructured materials; niobium alloys; samarium alloys; sintering; thermal stability; transmission electron microscopy; SmCo6.6Nb0.4; X-ray diffraction; bulk nanocrystalline magnet; coercivity; grain size; magnetic flux density 7 T; remanence; saturation magnetization; single-phase grain microstructure; spark plasma sintering; stable TbCu7 structure; temperature 773 K; thermal stability; transmission electron microscopy; Coercive force; Electrons; Magnetic materials; Niobium; Plasma materials processing; Plasma stability; Plasma x-ray sources; Saturation magnetization; Sparks; X-ray diffraction; Coercivity temperature coefficient; SmCo; nanocrystalline sintered magnet; spark plasma sintering (SPS);
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2007.900569
