Microwave absorption properties of Ba M-type ferrite prepared by a modified coprecipitation method

作者：Sugimoto S^*; Haga K; Kagotani T; Inomata K

来源：Journal of Magnetism and Magnetic Materials, 2005, 290: 1188-1191.

DOI：10.1016/j.jmmm..2004.11.381

• M-type ferrite
• coprecipitation
• microwave absorber
• reflection loss
• permeability

The electromagnetic wave absorption properties were investigated in the Co-Ti substituted Ba M-type hexagonal ferrites (BaFe9.5(Co1-yTiy)(2.5)O-19 (y = 0.4-0.8)), which were prepared by a modified coprecipitation method. This modified chemical coprecipitation method was the combination of coprecipitation and synthesis from a salt melt. The Ba-9.5(Co0.4Ti0.6)(2.5)O-19 sample, which was sintered at 1423 K for 5 h with a Bi2O3 addition of 2 wt%, exhibited high permeability (μ(r)&DPRIME;(max) = 25 and μ(r)&DPRIME; at 1 Ghz = 10). This sample also showed a good microwave absorption property (reflection loss: RL < -20 dB) with a small matching thickness (d(m)) of 3.1 mm at 0.65 GHz. It is concluded that the Ba M-type ferrite prepared by the modified coprecipitation method has a possibility to become a candidate for thinner microwave absorbers in the gigahertz range. © 2004 Elsevier B.V.

• 出版日期2005-4