由于羰基铁粉具有温度稳定性好、吸收频带宽、可设计性强等优点，从而得到了广泛的研究与应用。对两种参数基本一致，但形貌各异的羰基铁粉（球状和树枝状）进行了电磁吸波性能测试，用以研究形貌对羰基铁粉电磁吸波性能的影响。实验结果表明，形貌对羰基铁粉的电磁吸波性能有非常大的影响。相比于球状羰基铁粉，树枝状羰基铁粉的最大反射损耗增加了94%，达到-47.14 dB。同时，对应于最大反射损耗的频率从球状羰基铁粉的11.88 GHz移动到树枝状羰基铁粉的6.44 GHz。这是因为树枝状形貌有利于形成不连续网络、增加对入射微波的漫反射、还可以带来更多的界面电荷极化，从而增强对电磁波的吸收强度。此外，本研究表明各向异性结构是提高介电常数和介电损耗获得轻质宽带吸波剂的有效途径。

Because carbonyl iron powder (CIP) has the advantages of good temperature stability, wide absorption band and strong design ability, it has been widely studied and used. In this paper, the electromagnetic wave absorption properties of two kinds of carbonyl iron powder which have the same basic parameters but different morphologies (spherical and dendritic) have been tested to study the influence of morphology on the absorption properties of carbonyl iron powder. The experimental results show that the morphology of carbonyl iron powder has a great influence on the electromagnetic wave absorption performance. Compared to the spherical CIP, the maximum reflection loss(RL) of the dendritic CIP increases by 94%, reaching -47.14 dB. Moreover, the frequencies corresponding to the minimum RL values of absorption peaks shift form 11.88 GHz (spherical CIP) to 6.44 GHz (dendritic CIP). This is because the dendritic morphology is conducive to form discontinuous network, increase the diffuse scattering of incident electromagnetic wave as well as form more interfacial charge polarization, resulting in enhancing the absorption intensity of electromagnetic wave. In addition, this study shows that the anisotropic structure is an effective way to improve the dielectric constant and dielectric loss, and obtain the absorber with the characteristics of wide absorption bandwidth and light weight.

国家自然科学资助项目基金（No.61203098）；国网重庆市电力公司电力科学研究院资助项目（SGCQDK-00JS1500117）。