Carbon fabric composite is used in technical applications such as aircrafts in which electromagnetic shielding (electromagnetic interference–shielding effectiveness) is required. Traditionally, metallic coatings or metal plates are used for electromagnetic shielding, however, conductive filler-filled composite is also alternative to metal sheets due to its light weight. In the literatures, there are studies about effect carbon nanotube and graphene oxide flakes on electromagnetic interference; however, there are no studies encountered that search the effect of carbon nanotube/graphene oxide fiber and alignment of graphene oxide fiber on electromagnetic interference. Thus, in this study, fabrication of light-weight carbon fabric/epoxy composite filled with graphene oxide fiber, reduced graphene oxide fiber and multiwalled carbon nanotube and alignment of graphene oxide fiber was studied for the first time for both electromagnetic shielding (electromagnetic interference–shielding effectiveness) and electrical conductivity. It was found that reduced graphene oxide with two layers at the same alignment (0–0) leads to increment in the electromagnetic interference–shielding effectiveness value, while reduced graphene oxide with opposite alignment (0–90) leads to decrease in the electromagnetic interference–shielding effectiveness value. Opposite to literatures for graphene oxide flakes, highly rough surface of graphene oxide fiber and reduced graphene oxide fiber causes a deterioration in electromagnetic interference–shielding effectiveness due to disruptive multiple reflections resulted from highly rough surface of graphene oxide fiber, which causes multiple reflection effect. Multiwalled carbon nanotube generally provides higher electromagnetic interference–shielding effectiveness than graphene-based fiber because it has higher conductivity and has no disruptive effect of crimpy surface as graphene oxide fiber. Multiwalled carbon nanotube loading of 15 wt% results to 32 dB electromagnetic interference–shielding effectiveness, which is considered an adequate and moderate level of shielding for many applications.
