Magnetic, dielectric, and microwave absorbing properties of iron particles dispersed in rubber matrix in gigahertz frequencies
Magnetic, dielectric, and microwave absorbing properties of iron particles dispersed in rubber matrix in gigahertz frequencies
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DOI：
10.1063/1.1852371
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发表时间：
2005-05-15
影响因子：
3.2
通讯作者：
Lee, KS
中科院分区：
文献类型：
--
作者：
Kim, SS;Kim, ST;Lee, KS
本文研究了分散在橡胶基体中的铁颗粒的高频磁性、介电性和微波吸收性能，以制备千兆赫频率的薄微波吸收器。采用磨粒机对球形铁粉进行机械锻造，制备了含薄片状铁颗粒的复合材料，获得了较高的磁导率和介电常数。这是由于涡流损耗减少（磁导率增加）和空间电荷极化增强（介电常数增加）。然而，如果初始粒径过小（接近趋肤深度），则不会观察到增加磁导率的磨铣效应，并预测其介电常数较低。如果粒径过大，则由于涡流损耗强，磁导率值过小。通过控制铁颗粒的大小和形状（薄片）作为吸波填料，在1-2 GHz的反射损耗为-5 dB的情况下，厚度可降低至1 mm。(c) 2005年美国物理研究所。
This study investigates high-frequency magnetic, dielectric, and microwave absorbing properties of iron particles dispersed in rubber matrix for the aim of thin microwave absorbers in gigahertz frequencies. High value of magnetic permeability and dielectric constant can be obtained in the composites containing thin flake iron particles which were prepared by mechanical forging of spherical iron powders using an attrition mill. The results are attributed to the reduction of eddy current loss (increase of permeability) and enhancement of space-charge polarization (increase of permittivity). However, if the initial particle size is too small (approaching to skin depth), milling effect for the increase of permeability is not observed and a low dielectric constant is predicted. If the particle size is too large, the permeability value is too small due to strong eddy current loss. With the iron particles controlled in size and shape (flakes) as the absorbent fillers, the thickness can be reduced as low as 1 mm with respect to -5 dB reflection loss in 1-2 GHz. (c) 2005 American Institute of Physics.