片状Fe_4N磁粉复合材料的传导噪声抑制特性研究

Study on Conduction Noise Suppression Properties of Flaky Fe_4N Magnetic Powder Composites

将原料铁粉扁平化、退火、氮化处理后,制备扁平化Fe4N粉体,采用流延工艺将片状Fe4N磁粉与聚乙烯醇缩丁醛（PVB）以适当的比例混合均匀,制备电磁噪声抑制片,并用微带线方法对样品的传导噪声抑制特性进行了表征。结果表明,经过扁平化工艺和退火工艺的磁粉制备出的电磁噪声抑制片的传导噪声抑制效果良好,抑制特性随着磁粉含量以及噪声抑制片厚度的增加而提高,磁粉含量为80wt%、厚度为0.5 mm的样品的功率损耗比在2-10 GHz范围内达到90%以上,6-10 GHz时达到97%,能满足高性能吉赫兹频段宽频带电磁噪声抑制片的应用需求。

Iron powder was selected as raw material, the Fe_4N powder was prepared after milling process, annealing process and nitriding process.The flake Fe_4N magnetic powder and the polyvinyl butyral（PVB） were mixed in an appropriate ratio by typecasting technique to prepare the electromagnetic noise suppression sheet.Its conducted-noise suppression effect was measured by the micro-strip line method.The results showed that the conduction noise suppression capability of the electromagnetic noise suppression sheet performed well after milling process and annealing process, the conduction noise suppression properties are improved with the increase of either magnetic powder content or sheet thickness, and that the power loss ratio of the sheet with thickness of 0.5 mm and 80wt% magnetic powder is more than 90% in the frequency range of 2~10 GHz, in the frequency range of 6~10 GHz it can reach 97%, which can satisfy the application requirements of high-performance in wide-band giga-hertz frequency.