Expandable Graphite Preparation And Performance For Infrared / Millimeter Wave Interference Materials

This paper based on the interrelated theory of attenuating IR and MMW, and used expanded graphite as interfering material. This experiment prepared different kind of expansive graphite which had different granularity and inserted substances. Testing and analyzing the factors which affect the expanding rate, the effects on expanded volume of the granularity of expanding graphite, the inserted substances kinds and the expansive temperature were discussed. This experiment mainly researched the attenuation capability to IR/MMW of the different kind of expanded graphite which had prepared. Examining and analyzing the relationship between the factors(granularity,density,inserted substances kinds,the worm state)and the attenuation capability to IR/MMW, and various factor parameters of optimal attenuation effects were obtained. The results indicated that expanded graphite interfering effect on MMW is obvious, the signal of 3mm and 8mm transmission system is over 20dB. So was it effect on IR, especially at 3333-2000cm^-1 (3-5μm) wave number, IR transmittance was about 20%. Basing on the results of the examinations this paper used essential principles primarily analyzes and researches the principles of the attenuating capability of expanded graphite. Furthermore, this paper appended some additive to enhance the attenuation capability to IR/MMW. The results indicated that for MMW the best additive was SiC, and for IR the best additive was Fe₃O₄。...