EMI shielding effectiveness of metal-coated carbon fiber-reinforced ABS composites

EMI shielding effectiveness of copper- and nickel-coated carbon fiber-reinforced ABS composites was investigated. The coaxial transmission line method was used to measure the EMI shielding effectiveness of the metal-coated carbon fibers/ABS composites. The carbon fibers were coated with copper or nickel using the cementation and electroless deposition techniques. Measurements of fiber length distribution in the composites indicated that the length of copper-coated carbon fibers was shorter than that of nickel-coated carbon fibers after composite fabrication. As a result, their composites also showed poor EMI shielding effectiveness. Among the metal-coated carbon fibers/ABS composites studied in this investigation, electroless nickel-coated carbon fibers/ABS composites showed the best EMI shielding capability due to longer fiber length distribution and excellent bonding between nickel coating and the fibers. The metal coatings, deposited using the cementation technique, tended to detach from the fibers during the compounding process, and consequently, poor EMI shielding effectiveness was obtained for their composites.