1986 Fiscal Year Final Research Report Summary
Fabrication of Electromagnetic Absorber Composed of Ferrite Particles with Shape Anisotropy
| Project/Area Number |
60850147
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| Research Category |
Grant-in-Aid for Developmental Scientific Research
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| Allocation Type | Single-year Grants |
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| Research Field |
無機工業化学
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| Research Institution | Keio University |
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Principal Investigator |
YAMAGUCHI Takashi Faculty of Science and Technology, Keio University, 理工学部, 教授 (90051226)
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| Co-Investigator(Kenkyū-buntansha) |
成宮 義和 TDK株式会社, フェライト研究部
KIMURA Toshio Faculty of Science and Technology, Keio University, 理工学部, 専任講師 (70090040)
NARUMIYA Yoshikazu Ferrite Products, R & D, TDK Electronics
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| Project Period (FY) |
1985 – 1986
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| Keywords | Electromagnetic absorber / Shape anisotropy / NiZn-ferrite / MnZn-ferrite / 電磁シールド材料 |
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| Research Abstract |
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.
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