电磁屏蔽机理及涂敷/结构型吸波复合材料研究进展

Research Progress of Electromagnetic Shielding Mechanism and Coated/Structural Absorbing Composite Materials

电子产品和通讯技术快速发展造成的电磁污染日益严重,既危害人体健康和仪器仪表精度,又会造成信息泄露、失去安全保障等。因此,电磁屏蔽技术为直接有效的防控措施之一,通过衰减甚至完全消除电磁波来阻止电磁波的传递。电磁屏蔽机理包括电磁波反射和电磁波吸收两个方面,科学地设计制备出高性能的吸波复合材料已成为研究的热点问题之一。研究结果表明,电磁波衰减不仅需要吸波材料自身较好的电磁损耗性能,更需电磁波能够基于自由空间与基体材料间具有阻抗匹配特性,有效进入吸波材料内部,使电磁波能被吸波剂高效吸收。通常,按照制备工艺划分,吸波复合材料可分为涂敷型和结构型吸波复合材料两大类。前者是将吸波剂与涂料、粘合剂等充分混合后涂敷于元件表面作为吸波涂层,而后者则是以吸波剂作为功能载体,具有优良物理化学特性的材料作为基体,并与功能载体产生协同或增强作用的新型吸波复合材料。本文通过对电磁屏蔽理论及吸波材料的本征特性进行系统的总结归纳,并基于相关理论基础对涂敷/结构型吸波复合材料进行简要综述,对比不同类型吸波材料的吸波性能,探讨涂敷/结构型吸波复合材料未来发展的制约因素及今后发展前景,为开发新型吸波复合材料提供理论支撑和研究思路。

The increasingly serious electromagnetic pollution was caused by the rapid development of electronic products and communication technology,which not only endangers human health and instrument precision,but also causes information leakage and loss of safety guarantee.Electromagnetic shielding technology is one of the direct and effective prevention and control method,which can prevent the transmission of electromagnetic waves by attenuated or even completely eliminate electromagnetic waves.The mechanism of electromagnetic shielding includes electromagnetic wave reflection and electromagnetic wave absorption.The scientific design and preparation of high-performance absorbing composite materials has become one of the hot issues in research.The results show that the electromagnetic wave attenuation not only requires an excellent electromagnetic loss performance of the absorbing material,but also requires the electromagnetic wave to be able to effectively enter into the absorbing material based on the impedance matching characteristics between the free space and the matrix material,so that the electromagnetic wave can be efficiently absorbed by the absorbing agent.Generally,according to the preparation process,absorbing composites can be divided into coated absorbing composites and structural absorbing composites.The former is fully mixed with absorbing agents,paints,adhesives,etc.,and then coated on the surface of the components as absorbing coatings,while the latter is a new type of absorbing composites which uses absorbing agent as the functional carrier,materials with excellent physical and chemical properties as the matrix,and has synergistic or enhanced effect with the functional carrier.This paper systematically summarizes the electromagnetic shielding theory and the intrinsic characteristics of the wave absorbing materials,and briefly reviews the coated/structural absorbing composite materials based on related theoretical basis,comparing the absorbing properties of different types of absorbing materials,discusses coating/structural absorbing composite materials for the future development of restricting factors and the future development prospect.It provides theoretical support and research ideas for the development of new wave absorbing composites.