Al_2O_3对超细铁粉电磁性能影响的实验研究

Effect of Al_2O_3 on Electromagnetic Characteristics of Hyperfine Iron Powder

超细金属铁粉制备过程中加入Al2O3，使其抗氧化性能提高的同时，调整超细铁粉的电磁参数。本文采用自蔓延燃烧法制备不同成份比侧的Al2O3／Fe2O3复合物，并以此为原料采用氢气还原得到Fe／Al2O3金属复合粉。采用XRD、SEM、DSC-TGA等手段分析其结构、形貌和抗氧化性能，通过矢量网络分析仪确定其电磁参数在2—18GHz范围内的变化情况。结果表明：当复合粉末中Al2O3为10％时，粉末的抗氧化性能得到明显提高，在2—18GHz范围内其介电常数的实部和虚部得到了有效调整。

In order to improve the anti-oxidation and electromagnetic characteristics of the hyperfine iron powder, Al2O3 was added during the preparation of the powder. In the paper , the method of SHS was used to produce different componential Al2O3/Fe2O3 composite powder, which was deoxidized into Fe/Al2O3 composite metal powder by hydrogen later. The distinct characterization and anti-oxidation were investigated by X-ray diffraction （ XRD）, Scan electron microscopy （ SEM）, DSC-TGA and so on. The electromagnetic parameters were measured by Agilent micromave network analyzer in the range of 2 to 18GHz. Results have showed that when 10% Al2O3 was added into the hyperfine iron powder,its anti-oxidation could be improved obviously ,with its real and image part of permittivity to be rectified effectively.