Fabrication of Electromagnetic Absorber Composed of Ferrite Particles with Shape Anisotropy

形状各向异性铁氧体颗粒电磁吸波体的制备

• 批准号: 60850147
• 负责人: YAMAGUCHI Takashi
• 金额: $ 3.2万
• 依托单位: Keio University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60850147/
• 关键词: Electromagnetic absorber; Shape anisotropy; NiZn-ferrite; MnZn-ferrite; 電磁シールド材料

A wide-band electromagnetic absorber composed of ferrite particles with shape anisotropy has been described.Conditions for obtaining acicular and platy ferrite particles by the flux method were determined. Ferrite-polymer composites were prepared and electromagnetic absorption was evaluated in comparison with those from equiaxed ferrite particles.1) Micaceous <Fe_2> <O_3> particles with average diameters ranging 0.3 to 20 <micro> m were prepared by the flux or hydrothermal method, and they were converted to NiZn or MnZn ferrite under the appropriate conditions with their original shape preserved. Fine NiO and KCl were essential for NiZn ferrite, and a high melting-point flux like <K_2> <SO_4> and <N_2> atmosphere were required for MnZn ferrite. The optimum preparation temperature was 900゜ and 1150゜C for NiZn and MnZn ferrite respectively.2) Ferrite-polymer composites exhibited a wider and lower resonance frequency than those prepared from equiaxed ferrite particles with the same average particle size.

介绍了一种由形状各向异性铁氧体颗粒组成的宽带电磁吸波材料，确定了用助熔剂法制备针状和片状铁氧体颗粒的条件。制备了铁氧体-聚合物复合材料，并与等轴铁氧体颗粒的电磁吸收性能进行了比较。1）<Fe_2><O_3><micro>采用助熔剂法或水热法制备了平均粒径为0.3 ~ 20 μ m的云母颗粒，并在适当的条件下将其转化为NiZn或MnZn铁氧体，保持其原始形状。NiZn铁氧体的制备需要精细的NiO和KCl，MnZn铁氧体的制备需要高熔点的助熔剂<K_2><SO_4>和<N_2>气氛。NiZn和MnZn铁氧体的最佳制备温度分别为900 ℃和1150 ℃。2）铁氧体-聚合物复合材料比相同平均粒径的等轴铁氧体颗粒制备的材料具有更宽和更低的谐振频率。

项目成果

Y. Hayashi, T. Kimura and T. Yamaguchi: "Mechanism of Ni-Zn Ferrite Formation in the Presence of Molten <Li_2> <SO_4> - <Na_2> <SO_4> " J. Am. Ceram. Soc.69. 322-325 (1986)

Y. Hayashi、T. Kimura 和 T. Yamaguchi：“熔融 <Li_2> <SO_4> - <Na_2> <SO_4> 存在下 Ni-Zn 铁氧体形成的机制” J. Am.

Y.Hayashi: J.Mater.Sci.21. 2876-2880 (1986)

Y.Hayashi：J.Mater.Sci.21。

Amer.Ceram.Soc.Bull.64-9. (1985)

Amer.Ceram.Soc.Bull.64-9。

T.Kimura: Adv.Ceram.21. (1987)

T.Kimura：Adv.Ceram.21。

T. Kimura and T. Yamaguchi: "Morphology Control of Electronic Ceramic Powders by Molten Salt Synthesis" Adv. Ceram.21. (1987)

T. Kimura 和 T. Yamaguchi：“熔盐合成对电子陶瓷粉末的形态控制”Adv。