Title :
Effects of Solution Treated Temperature on the Structural and Magnetic Properties of Iron-Rich
Sintered Magnet
Author :
Horiuchi, Yoichiro ; Hagiwara, Manabu ; Okamoto, K. ; Kobayashi, Takehiko ; Endo, Miyuki ; Kobayashi, Takehiko ; Nakamura, T. ; Sakurada, Shinya
Author_Institution :
Corp. R&D Center, Toshiba Corp., Kawasaki, Japan
Abstract :
The effects of solution-treatment temperature on the phase constitution, microstructure and magnetic properties of Sm(Cobal.Fe0.35Cu0.06Zr0.018)7.8 were investigated systematically. The formation of Sm2Co7 around the Sm2O3 was confirmed and the volume fraction of Sm2Co7 increases with decreasing solution-treatment temperature. An area without cellular structure was observed around the Sm2Co7 phase in aged specimens solution treated at 1403 K. Thus, it was found that precipitation of Sm2Co7 phase prevents the formation of cellular structure during aging treatment. The coercivity of those magnets was less than 600 kA/m. On the other hand, the obvious formation of cellular structure was confirmed in the case of solution treatment at 1423 K and these magnets showed high coercivity of more than 1000 kA/m. The magnetic properties of Mr = 1.22 T and HcJ = 1011 kA/m have been obtained for Sm(Cobal.Fe0.35Cu0.06Zr0.018)7.8 by solution treatment at 1423 K.
Keywords :
ageing; cobalt alloys; coercive force; copper alloys; crystal microstructure; iron alloys; precipitation; samarium alloys; sintering; zirconium alloys; Sm(CoFeCuZr)z; Sm2Co7; Sm2O3; aging treatment; cellular structure; coercivity; iron-rich sintered magnet; magnetic properties; microstructure; phase constitution; precipitation; solution treated temperature; structural properties; temperature 1403 K; temperature 1423 K; Aging; Coercive force; Iron; Magnetic properties; Microstructure; Temperature; $({rm Sm}_{2}{rm Co}_{17})$ phase; ${rm Sm}({rm CoFeCuZr})_{rm z}$ magnet; Cellular structure; coercivity; solution treatment;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2013.2247576