Effects of Hollow Carbon Fiber on the EMI

There are nowadays so many sophisticated and sensitive electrical instruments and equipment exposed to environmental storms of electromagnetic waves.Through that some error operations or catastrophic accidents could be occurred. Therefore they need urgently electromagnetic interference (EMI). For this purpose, conventional metallic interference materials were still used, while new more effective and fair materials such as conductive plastic composites are now available or on the threshold of developing. The effective EMI is basically due to high electro conductive characteristics with low skin depth. We have first 1990 developed C- and hollow-shaped carbon fiber from mesophase pitch which showed not only excellent mechanical properties and flexibility, but also higher thermal anisotropic factor than that of the round carbon fiber(more the 2 times). Now in this study, we have investigated the shielding effectiveness of C- and hollow- carbon fiber, because we believe that, hole effects and thermal anisoproperties on the radiation reflectivity, transmissivity and dissipation will be excellent.