基于磷化处理和双马来酰亚胺包覆铁粉的高性能磁粉芯的工艺优化  

Process optimization of high-performance soft magnetic composite based on phosphate and bismaleimide coated iron powders

作　　者：余红雅 关少聪[2,3] 李竞舟 刘仲武 郭宝春[1,2,3] 陈榕寅 YU Hongya;GUAN Shaocong;LI Jingzhou;LIU Zhongwu;GUO Baochun;CHEN Rongyin(Dongguan Mentech Optical&Magnetic CO.,LTD.,Dongguan 523330,China;School of Materials Science and Engineering,South China University of Technology,Guangzhou 510640,China;South China Institute of Collaborative Innovation,Dongguan 523808,China)

机构地区：[1]东莞铭普光磁股份有限公司,东莞523330 [2]华南理工大学材料科学与工程学院,广州510640 [3]华南协同创新研究院,东莞523808

出　　处：《复合材料学报》2023年第4期2216-2223,共8页Acta Materiae Compositae Sinica

基　　金：东莞市引进创新科研团队项目(2020607231010);广东省自然科学基金面上项目(2021A1515012464)。

摘　　要：随着电子行业的迅速发展,电子器件正朝着小型化、集成化和高频化方向发展。磁粉芯材料会因应用频率提高引起磁损耗剧烈增加和严重发热而出现磁性能下降,磁粉芯材料的高频应用对其损耗特性和可靠性提出更高的要求。本文通过磷化处理和双马来酰亚胺树脂(BMI)包覆制备出了具有磷化-双马来酰亚胺@Fe结构的高性能磁粉芯,并研究了包覆方式对磁粉芯可靠性的影响。当BMI树脂添加量为2wt%,压制压力为800 MPa时,磁粉芯的综合磁性能最佳,有效磁导率为32.2,50 mT@200 kHz条件下的总损耗为1181 kW/m^(3),1 MHz条件下的品质因数Q可达到46.2。BMI树脂包覆形成的绝缘层可以起到应力缓冲的作用,减少压制过程中的内应力形成,降低磁粉芯的总损耗。傅里叶红外光谱分析证明磁粉芯的老化是由磁粉的氧化引起的,通过磷化处理和BMI树脂包覆能有效减缓磁粉氧化并提高磁粉芯的高温可靠性,经过180℃长期加速老化试验后,磁性能保持稳定。Electronic devices are developing towards miniaturization,integration,and high frequency with the development of electronic industry.The soft magnetic cores require better loss characteristics and higher reliability becaues their magnetic properties would decline due to the sharply increased magnetic loss and serious heating with the high-frequency application.In this work,high-performance soft magnetic composites with phosphate-bismaleimide@Fe structure were prepared by phosphating treatment and bismaleimide(BMI)coating,and the effects of insulation coating methods on the reliability of soft magnetic composites were investigated.The results indicate that the excellent comprehensive magnetic properties of soft magnetic composites have been obtained as the content of BMI resin is 2wt%and the compaction pressure is 800 MPa,the effective permeability is 32.2,the total loss is 1181 kW/m^(3)under the condition of 50 mT@200 kHz and the quality factor Q can reach 46.2 at 1 MHz.Moreover,it is found that the resin layer between iron powder particles can play a role of stress buffer to reduce the formation of internal stress and the total loss of soft magnetic composites.The aging of soft magnetic composites due to the oxidation of the magnetic powders which was proved by flourier infrared spectrum analysis.The phosphating treat-ment and BMI coating can effectively slow down the aging to improve the high-temperature reliability of soft magnetic composites and perform stable magnetic properties after long-term accelerated aging test at 180℃.

关 键 词：磁性材料 双马来酰亚胺 磷化处理 耐热性 磁损耗 磁粉芯 

分 类 号：TB331[一般工业技术—材料科学与工程]