異方性Ba-Zn系W型六方晶フェライト磁石の磁気特性に及ぼすCaO,SiO₂添加の影響

抄録

An experiment was carried out to investigate the effect of CaO and SiO₂ addition on the magnetic and physical properties of anisotropic Ba-Zn W-type hexagonal ferrite magnets. It was found that magnetic properties of BaO•2ZnO•8Fe₂O₃ compounds added with CaO and SiO₂ were improved. The optimum conditions of typical specimens are as follows: chemical analysis composition-Ba_0.857 Zn_1.643 Ca_0.150 Si_0.266 Fe²⁺_0.030 Fe³⁺_15.857 O₂₇; semisintering condition-1, 275°C×1.0h in air; sintering condition-1, 250°C×0.5h in air; magnetic and physical properties are J_m=0.436T, J_r=0.393T, H_cJ=64.4kA/m, H_cB=64.1kA/m, (BH)_max=16.1kJ/m³, T_c=357°C, H_A=971kA/m, K_A=2.03×10⁵J/m₃ and n_B=33.2μB.