Title :
Characterization of nitrogenation of Sm2Fe17
Author :
Fukuno, Akira ; Ishizaka, Chikara ; Chihara, Hiroshi ; Yoneyama, Tetsuhito
Author_Institution :
TDK Corp., Chiba, Japan
fDate :
9/1/1992 12:00:00 AM
Abstract :
The role of hydrogen treatment before nitrogenation of Sm2 Fe17 and the relation between nitrogenated conditions and nitrogen contents are examined. Many cracks occur in Sm2Fe17 particles during the hydrogenation process, and it is thought that hydrogen treatment increases the gas-solid reaction area significantly. The lower-temperature and longer-time nitrogenations are effective in reducing the amount of α-Fe phase, which decreases the hard magnetic properties. The analysis of nitrogen contents in a particle by EPMA (electron probe microanalysis) and experiments on magnetic properties show that it is important to obtain homogeneous Sm2Fe17Nx powder in order to make high-performance magnets. High-coercivity (12 kOe) and high-energy (28 MGOe) products were obtained as fine powders by optimizing the nitrogenation conditions
Keywords :
X-ray diffraction examination of materials; coercive force; electron probe analysis; ferromagnetic properties of substances; iron alloys; magnetic properties of fine particles; magnetisation; nitridation; permanent magnets; powder metallurgy; samarium alloys; scanning electron microscope examination of materials; thermal analysis; 450 to 600 C; EPMA; SEM; Sm2Fe12Nx powder; X-ray diffraction; coercivity; differential thermal analysis; electron probe microanalysis; energy product; fine powders; gas-solid reaction; hard magnetic properties; high-performance magnets; hydrogenation process; magnetisation; nitrogenation; Argon; Atmosphere; Atmospheric measurements; Iron; Nitrogen; Powders; Samarium; Scanning electron microscopy; Temperature; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
