Magnetic Properties of Sm-Nd-Fe-Co-N Compounds and Their Bonded Magnets

Experiments were carried out to investigate the magnetic and physical properties of (Sm1-xNdx)2(Fe0.8Co0.2)17Ny (x=0 to 0.5) in which the value of y is 3. The anisotropy field (HA) in (Sm1-xNdx)2(Fe0.8Co0.2)17Ny compounds decreased linearly with increasing x, while the saturation magnetization (Js) increased. It was found that the HA and Js of a (Sm0.9Nd0.1)2(Fe0.8Co0.2)17N3.07 compound were 10.4 MA/m and 193.6×10^¿6 Wb-m/kg respectively. Anisotropic epoxy-bonded magnets were prepared from (Sm0.9Nd0.1)2(Fe0.8Co0.2)17N3.07 powder with particle size ranging from 3 to 5 ¿m by a compression molding process. The magnetic properties of a typical bonded magnet were (BH)max=101.8 kJ/m³, Jr=0.89 T, HcJ=394 kA/m, and HcB=314 kA/m. Magnetization jumps were observed on the hysteresis loop of a bonded magnet at 7K.