Composite material for emi/emp hardening protection in marine

Abstract

Composite material composed of conducting and semi-conducting oxide partis, fibers, or flakes suspended in a of polymeric material matrix for use in connectors, junction boxes, enclosures or similar electromagnetic shielding applications. The use of a composite material with electromagnetic shielding properties built into the material itself, combined with the use of a semi-conductive filler that minimizes the corrosive effect of an electrochemical potential difference, provides EM shielding and corrosion resistance for these materials when they are used in marine and aircraft environments. Oxide semiconductor materials and compatible conductive fillers also provides a basis for a new class of EMI and EMP composite materials that exhibit a stable current-controlled and voltage-controlled negative resistance (VCNR, CCNR) characteristic. Testing has shown that the conductivities of these materials increase as the field and/or the voltage increases. This characteristic is desirable, providing inherent protection of electronic circuits from voltages or currents. This VCNR/CCNR effect is dependent upon the voltages, the degree of filler material combinations and the filler loading which will determine the composite materials properties.