Abstract
Effects of the preparation condition on magnetic properties were investigated in isotropic TbCu7-type Sm-Zr-Fe-Co-N materials made by the melt-spinning process. All the Sm-Zr-Fe-Co powders melt-spun with wheel speeds of 30-40 m/s showed a single-phase structure with crystalline TbCu7. The grain size of the powder decreased monotonically with the increase of the wheel speed. The HcJ, Br and (BH) max of the powder increased with decreasing grain size. In this study, maximum hard magnetic property was achieved in Sm 8.7 Zr 1.0 Fe 85.8 Co 4.5 Nx powder melt-spun at 40 m/s. A compression-molded bonded magnet using powder melt-spun with at a wheel speed of 40 m/s showed excellent hard magnetic properties: Br=0.83 T, HcJ=720.5 kA/m, (BH) max=113.9 kJ/m 3. These results show that the TbCu7-type Sm-Fe-N material has high performance and practicality for isotropic bonded magnets.
