Extrinsic permeability of Fe-based flake composites from intrinsic parameters: A comparison between the aligned and random cases
Extrinsic permeability of Fe-based flake composites from intrinsic parameters: A comparison between the aligned and random cases
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DOI：
10.1016/j.jmmm.2011.08.032
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发表时间：
2012-02
影响因子：
2.7
通讯作者：
Tao Liu;P. Zhou;Jianliang Xie;L. Deng
中科院分区：
文献类型：
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作者：
Tao Liu;P. Zhou;Jianliang Xie;L. Deng
由铁磁片镶嵌在非磁性基质中形成的复合材料作为一种很有前途的微波材料，受到了人们的广泛关注。本文以吉赫兹为单位，测量了夹杂物空间取向均匀分布和随机分布的铁基纳米晶片组成的复合材料的有效磁导率。在薄片上涂覆一层薄的二氧化硅，以降低介电常数和改善阻抗匹配。研究发现，薄片的磁损耗主要是由自然铁磁共振和交换共振引起的。为了探索未解决的对准情况下有效渗透率的计算问题，结合Landau-Lifshitz-Gilbert方程和Maxwell-Garnett混合规则，对复合材料的有效渗透率谱进行了预测。与实验结果的很好吻合表明了所提出的理论方法的有效性。
Composites consisting of aligned ferromagnetic flakes embedded in a nonmagnetic matrix are the focus of attention as a kind of promising microwave material. In this paper, the effective permeability for composites consisting of nanocrystalline Fe-based flakes with aligned and random spatial orientation distribution of inclusions for comparison is measured in gigahertz. Flakes were coated with thin silica layer to reduce permittivity and improve impedance match. It is found that the magnetic loss in flakes is mainly caused by the natural ferromagnetic resonance and exchange resonance. To explore the unsolved problem of calculating effective permeability for the aligned case, the combination of Landau–Lifshitz–Gilbert equation and Maxwell–Garnett mixing rule with important modification is used to predict the effective permeability spectrum of composites. An excellent agreement with the experiment results indicates the validity of proposed theoretical approaches.