Electromagnetic Interference Behavior of Multiwall Carbon Nanotubes and Carbon Nanofibers Composites Under Fatigue.

摘要

The United States military is researching the use of nanocomposite materials for structural applications on space vehicle systems. To reduce vehicle weight and mitigate the electromagnetic interference (EMI) brought on by the harsh space environment, today's space vehicles are made of composites coated with expensive conductive materials. Research on composites made of carbon nanotubes (CNT) and carbon nanofibers (CNF) has shown better EMI shielding performance with these materials compared to the current composites coated with expensive conductive materials. Thus, CNTs and CNFs offer the potential to replace the current composites. This study evaluated the effects of EMI behavior on one control composite (i.e., without nanocomposite) and five different configured nanocomposites under fatigue. The control specimen, 8G, consisted of eight plies S-glass (Astroquartz II) fiber in CYCOM 5575-2 cyanate ester matrix. The first nanocomposite, 8G/CNT, consisted of eight plies of 6781 S-2 glass fiber in CYCOM 5250-4 Bismaleimide (BMI) matrix with an externally deposited layer of CNTs. The second nanocomposite, 8G/CNF, consisted of eight plies of 6781 S-2 glass fiber in CYCOM 5250-4 BMI matrix with an externally deposited layer of CNFs. The last three nanocomposites, (G/CNT)4, 2CNT/4G/2CNT, and 4G/4CNT, consisted of different stacking sequences of multi-wall CNTs (MWNT) with S-glass (Astroquartz II) fiber in CYCOM 5575-2 cyanate ester matrix.