Nickel fiber silicone-matrix composites as resilient electrical conductors

Short nickel fiber silicone-matrix composites containing 3-12 vol.% fibers were fabricated by the impregnation of silicone into a nickel fiber preform. The composites exhibited volume electrical resistivity ranging from 4.5 × 10^-4 to 2.8 × 10^-3 ohm.cm, contact electrical resistivity (with copper at a pressure ≥ 0.1 MPa) ranging from 0.0090 to 0.0155 ohm.cm², permanent set ranging from 0.3% to 0.6% after compression to a stress of 0.4 MPa and a strain of 6%-13.5%, and electromagnetic interference (EMI) shielding effectiveness > 50 dB at 1.0 - 2.0 GHz. The volume and contact resistivities were essentially not affected after heating in air at 130-150°C for 7 days. These resilient electrically conducting composite are useful for electrical contacts and for gaskets for EMI shielding.