抄録
Experiments were carried out to investigate the magnetic properties of Sm-Fe-Co-Nb-Zr system nitriding compounds with TbCu7-type structure. Sm8(Fe0.95Co0.05)88.0Nb4.0-xZrx (X=0-4) alloy ribbons were prepared by the single roller rapid-quenching method, and the effects of alloy composition, and conditions of heat-treatment and nitrogenation, were examined with regards to their magnetic properties. The optimum preparation conditions of the compounds are as follows. Composition: {Sm8(Fe0.95Co0.05)88.0Nb3.0Zr1.0}86.7N13.3, roller velocity: 50m/s, heat treatment: 725°C×60 min in high-purity Ar atmosphere, and nitriding condition: 400°C×15h in high-purity N2 gas. Typical magnetic properties of the obtained compound are HcJ=678.0 kA/m (8.52 kOe), σr= 120.0×10-6 Wb·m/kg (91.64 emu/g), σ1.6M =162.1×10-6 Wb·m/kg (129.0 emu/g), (BH)max=123.4 kJ/m3 (15.5 MGOe), and Tc= 508°C. The value of (BH)max for the compression-molded isotropic bonded magnet prepared from the {Sm8(Fe0.95Co0.05)88.0Nb3.0Zr1.0}86.7N13.3 powder is 81.1 kJ/m3(10.2 MGOe), when the density of the bonded magnet is 5.9 Mg/m3.
