異方性Ca-La-Nd系フェライト磁石の諸特性

抄録

Experiments were carried out to obtain the optimum condition for preparing anisotropic Ca-La-Nd ferrite magnets having the best magnetic and physical properties. The best composition was pursued according to the formula {(100-X)(CaO·6Fe₂O₃)} {X(70%La₂O₃)}, varring X from 1.0 to 13 wt%. The samples used in this experiment were prepared by mixing of the raw materials of a-Fe₂O₃, CaCO₃, and 70% La₂O₃ (contains 20% Nd₂O₃) powder. The optimum condition of making magnets and some properties of atypical specimen are as follows. The preparation condition: composition of {92(CaO·6Fe₂O₃)8(70%La₂O₃)}, prefiring condition of 1225°C for 1 h in O₂ gas and sintering condition of 1250°C for 0.5h in O₂ gas. Magnetic and physical properties.: 4πI10k=4100G, 4πIr=3900G, IHc=1800 Oe, BHH=1760 Oe, (BH)max=3.6 MG·Oe, Ku=3.3×10₆ erg/cc, HA=20.0 kOe, as=65.0 emu/g, Tc=451°C and D=5.07 g/cc.