EFFECTS OF CARBON FIBER ORIENTATION ON ELECTROMAGNETIC INTERFERENCE SHIELDING PERFORMANCES

Abstract

The high thermal-conductive carbon fiber is a promising electromagnetic interference (EMI) shielding material. This material is gaining popularity in building construction as it is corrosion resistant, has high tensile strength, is light weight and low in cost as compared to commonly used metal shielding which is heavy weighted and prone to EMI leakage at joints of building structures. This paper presents the investigations of EMI shielding effectiveness on multilayer carbon fiber composite with different orientations. Three concrete samples are considered in different orientations and are experimentally tested via shielding effectiveness (SE). The SE experiment set-up consists of a planar sample with its input and output connected to a vector network analyzer (VNA) in the frequency range of 3.0 GHz to 4.2 GHz. Based on the conductivity measurements of different orientations, the shielding effectiveness is obtained as a function of frequency as the plane wave analysis correlates the conductivity and shielding effectiveness measurements. It is proven that the carbon orientation contributes to changes in conductivity due to the positioning of the electric field of the incident wave and thus, produces different shielding performances.