纳米晶化处理对抗EMI材料电感特性的影响

The Influence of Nanocrystallization Process on Inductance Characteristics of Fe-based Electromagnetic Interference materials

解决现代通信和开关模式网络中的电磁干扰是近期国内外关注的焦点 ,利用磁性材料特别是纳米晶软磁材料研究开发成无源抗 EMI器件是解决这一问题的得力途径。但就纳米晶抗 EMI材料研究方面 ,目前存在两个方面的主要问题 :第一 ,非晶丝带纳米晶化后脆化问题 ;第二 ,内绝缘层与磁耦合问题。就上述两个问题进行研究。首先对非晶材料进行不同晶化处理工艺 ,如真空炉退火 ,快速冷却退火 ,快速循环退火 ,使晶粒细化到 2 0～ 3 0 nm,电感 L值有所提高。其次对材料采用不同的内层绝缘材料 (如 PI+Si O+铁氧体和 PI+铁氧体 )和退火先后涂膜进行对比。最后测试磁芯电感 L =6 8μH(1 0 k Hz) ,3 5μH(1 0 MHz)

It is very important to solve the problem of electromagnetic interference(EMI) existing in electronic communication and high frequency switched mode power supplies. One of the most effective methods is to develop EMI filter using magnetic material, especially the nanocrystal magnetic material. According to the research on nano crystal material and EMI filter, there are still two main problems. The first is the brittleness of the nanocrystal layer after annealing. The second is the interlayer magnetic coupling and electric isolation techniques. This paper focuses our works on this two problems. First, we choose different crystallization process,such as vacuum annealing,rapid cooling annealing and rapid circulating annealing,so that the crystal size can be reduced to 20～30nm,and the induction can be increased. Second,comparison experiments were made on different interlayer isolation material,such as PI plus SiO 2 plus ferromagnetic,PI plus ferromagnetic. Finally,we acquired the results as follows: L =68μH(10kHz),35μH(10MHz).