Mechanical and electromagnetic shielding properties of carbon fabric with graphene nanoplatelets reinforced epoxy composites

In this work, carbon fabric-reinforced epoxy (CF/E) and carbon fabric/graphene nanoplatelets (1 wt%, 2 wt% and 3 wt%) reinforced epoxy (CF/GNP/E) laminates (one-layer, two-layer, and four-layer) were prepared using the hand layup method. Further, according to ASTM standards, the test samples were machined using abrasive waterjet machining, and tensile properties and hardness were studied. It was found that tensile strength modulus and strain-to-failure improved due to the addition of GNPs into the epoxy matrix in the composite; the CF/1GNP/E composite showed the highest tensile strength modulus and strain-to-failure. Further addition of GNPs of more than 2 wt% deteriorates the mechanical properties due to agglomeration. The electromagnetic interference shielding effectiveness by absorption and reflection of all the samples was investigated using the measured S-parameters in an X-band frequency range. The effectiveness of electromagnetic interference shielding increased with the addition of GNPs, and the multi-layer structure in the composites showed absorption-dominated electromagnetic shielding. The CF/3GNP/E 4-layer composite showed the highest (32.4dB) shielding effectiveness and was recommended for commercial application in the X-band frequency range.