Title :
Enhancement of magnetic properties of Fe3B/Nd2Fe14B magnet by the addition of Co
Author :
Yang, Choong Jin ; Park, Eon Byung ; Hwang, Yong Soon ; Kim, Eng Chan
Author_Institution :
Electromagn. Mater. Lab., Res. Inst. of Ind. Sci. & Technol., Pohang, South Korea
fDate :
9/1/1999 12:00:00 AM
Abstract :
The addition of Co was found to enhance the magnetic properties of Fe3B/Nd2Fe14B nanocomposite magnets by forming Nd4Fe77.5-xCox(HfGa)yB 18.5(0⩽x⩽5, 0⩽y⩽0.5). The enhancements resulted from the fact that the Co addition retarded the crystallization of a-Fe and Fe3B accelerated that of Nd2Fe14 B. The decreased interval between the crystallization temperature of Fe3B and Nd2Fe14B enabled the grain growth of each phase to be uniform during post annealing of the melt spun ribbons. The addition of Co from 3 to 5 wt.% increased the coercivity (iHc) from 3.27 3.54 kOe with the enhanced remanence (4 π Mr) around 11.54 kG. By the optimized processing for the nanocomposite magnets of Nd4Fe 71.5Co5Hf0.5Ga0.5B18.5 ribbons spun at 26 m/sec and magnetization annealing at 680°C for 10 min, the magnetic properties of Br1=11.54 kG, i Hc=3.54 kOe and (BH)max=14.35 MGOe were obtained from volume production line
Keywords :
alloying additions; annealing; boron alloys; cobalt alloys; coercive force; crystallisation; ferromagnetic materials; gallium alloys; grain growth; hafnium alloys; iron alloys; magnetic particles; nanostructured materials; neodymium alloys; permanent magnets; remanence; 10 min; 680 C; Co addition; Fe3B/Nd2Fe14B magnet; Fe3B/Nd2Fe14B nanocomposite magnets; Nd4Fe71.5Co5Hf0.5Ga 0.5B18.5 ribbons; Nd4Fe77.5-xCox(HfGa)y B18.5; NdFeCoHfGaB; coercivity; crystallization; crystallization temperature; enhanced remanence; grain growth; magnetic properties; magnetization annealing; melt spun ribbons; nanocomposite magnets; post annealing; volume production line; Acceleration; Annealing; Coercive force; Crystallization; Iron; Magnetic properties; Magnets; Neodymium; Remanence; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
