異方性BaFe_2-W型フェライト磁石の磁気特性 : 第1報 [in Japanese] Magnetic Properties of Anisotropic BaFe_2-W Type Ferrite Magnets : First report [in Japanese]
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An experiment was carried out to investigate the effect of Ba-Stearate as a reducing agent on the magnetic and physical properties of anisotropic BaFe<SUB>2</SUB>-W type ferrite magnets. It was found that the magnetic properties of BaO·8.5Fe<SUB>2</SUB>O<SUB>3</SUB> were improved by adding 0.3 wt% of Ba-Stearate, 0.5 wt% of SiO<SUB>2</SUB>, and 0.5 wt% of CaO together. The optimum conditions for making magnets were as follows; Chemical composition: Ba<SUB>1.029</SUB>Ca<SUB>0.127</SUB>Si<SUB>0.097</SUB>C<SUB>0.053</SUB>Fe<SUP>2+</SUP><SUB>2.456</SUB>Fe<SUP>3+</SUP><SUB>15.392</SUB>O<SUB>27</SUB>, semisintering condition: 1350°C×4.0 h in nitrogen gas atmosphere, drying condition: 180°C×2.0 h in air, sintering condition: 1160°C×1.5 h in nitrogen gas atmosphere. Magnetic and physical properties of a typical sample were J<SUB>m</SUB> = 0.46 T, J<SUB>r</SUB> = 0.43 T, H<SUB>cJ</SUB> = 182.3 kA/m, H<SUB>cB</SUB> = 177.2 kA/m, (BH)<SUB>max</SUB> = 33.8 kJ/m<SUP>3</SUP>, T<SUB>c</SUB> = 495°C, H<SUB>A</SUB> = 1332 kA/m and K<SUB>A</SUB> = 2.65×10<SUP>5</SUP>J/m<SUP>3</SUP>. The lattice constants of this compound were a = 5.883×10<SUP>−10</SUP>m, c = 32.92×10<SUP>−10</SUP>m, and c/a = 5.596.
- J. Jpn. Soc. Powder Powder Metallurgy
J. Jpn. Soc. Powder Powder Metallurgy 53(7), 602-609, 2006-07-15
Japan Society of Powder and Powder Metallurgy