Improving the through-thickness electrical conductivity of carbon fiber reinforced polymer composites using interleaving conducting veils

Abstract

In this study, thin carbon fiber-based conducting veils were used as interleaving materials to improve the through-thickness electrical conductivity of carbon fiber reinforced composites. Carbon fiber (CF) or nickel-coated carbon fiber (NiCF) veils were used as interlayers between standard carbon fiber reinforcement fabrics. The through-thickness electrical conductivity of the interleaved composites with CF or NiCF veils improved over 50 fold, from 0.18 to 9.47 and 9.16 S/cm, respectively, compared to the control specimens. However, the interleaved specimens exhibited a ca. 20%–24% reduction in their interlaminar shear strength (ILSS) and flexural strength. The introduction of conducting veils facilitated establishing an electrical pathway between the carbon fabric plies by reducing the non-conducting resin rich zone in the interlaminar region. This established an electrically conductive pathway across the thickness of the laminate. This study reveals that conducting veil-interleaved composites can meet a functional integration requirement of the aerospace sector for electrical properties, and can find applications in lightning protection, EMI shielding, and structural health monitoring.