磁性纳米复合材料的可调控宽带微波吸收机制研究

项目名称： 磁性纳米复合材料的可调控宽带微波吸收机制研究

项目编号： No.51301081

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 马骥

作者单位： 兰州大学

项目金额： 25万元

中文摘要： 磁性纳米复合材料，由于磁性纳米颗粒对微波的特殊吸收作用及具有高的电阻率、低的密度、电磁参数灵活可调等优点，近年来成为吸波材料领域研究的热点。目前，如何有效的调控和扩展吸收频带是这类材料在实际应用和研究中需要解决的重要问题。吸收频带的位置和带宽与共振频率和磁导率相关。根据铁磁性理论，改变磁性颗粒的成分和形状可改变其共振频率和磁导率，从而可对吸收频带进行调控和扩展。与传统理论不同，本项目将从"磁性纳米颗粒的尺寸变化将引起其表面各向异性和共振机制的改变"入手，通过改变颗粒尺寸，改变表面各向异性和有效各向异性，调控共振频率；通过研究颗粒尺寸变化引起的共振机制变化对磁谱的影响，调控磁导率。在此基础上研究磁性纳米复合材料的可调控宽带微波吸收机制，并最终获得频带可调的宽带吸波材料。宽带吸波材料的研发在基础研究，国防和民用技术方面都具有重要意义。本项目的实施将为其设计开发提供新的思路、理论指导和科学依据。

中文关键词： 磁性纳米复合材料；微波吸收；；；

英文摘要： Recently, much attention has been paid to magnetic nanocompistes as microwave absorbers due to their high resistivity, low density, adjustable electromagnetic parameters and special interactions between magnetic nanoparticles and microwaves. At present, from the fundmental research and application point of view, adjusting and broadening the microwave absorption band are the main problems for such nanocomposites as microwave absorbers. The location and bandwidth of absorption band of magnetic nanocomposties is closely related to the resonance frequency and complex permeability, both of which, based on the ferromagnetic theory, can be changed by changing the composition and shape of the magnetic particles. So the absorption band can be adjusted indirectly by changing the composition and shape of the magnetic particles. Compared to the methods mentioned above, however, this project will take another different ways to adjust the absorption band. For the adjustment of the resonance frequency, the effective anisotropy of magnetic nanoparticles is changed by changing their surface anisotropy through the change of the particle size. For the change of the values of the complex permeability, a new magnetic loss will be introduced in GHz frequency band by changing the particle size. Based on the above results, this project

英文关键词： magnetic nanocomposite；microwave absorption；；；