USA As Represented by Secretary of the Navy

David S Dixon

James V Masi

Nicholas F Schade

Michael D Obara

William G Bradley

A method of improving the electromagnetic (EM) shielding performance of a mposite material is provided. The composite material has conductive and semi-conductive filler particles suspended in a non-conductive resin. The filler particles can be up to 40 weight percent of the composite material. The composite material is electroplated with a conductive material onto a portion of its surface to improve the electrical connection between the conductive material and a portion of the filler particles. EM shielding performance can be further enhanced by injecting an exponentially decaying electromagnetic pulse through the composite material that has been electroplated.

Method for improving electromagnetic shielding performance of composite

A method of forming a composite material for EMI/EMP hardening protection at has a predictable EM shielding performance in terms of penetration depth is provided. A base material is doped with a predetermined volume fraction of filler particles such that the base material forms a separating contact region between each pair of adjacent filler particles. An electrical equivalent circuit for a filler particle pair and separating contact region is used to represent electrical properties associated with the filler particle pair and separating contact region. A network equivalent impedance of the base material doped with the filler particles is generated using the electrical equivalent circuit. The network equivalent impedance, dielectric constants of the base material and the filler particles, and the predetermined volume fraction of filler particles are used to predict the EM shielding performance of the base material doped with the filler particles in terms of penetration depth.

Method for providing EMI/EMP hardening and breakdown protection in

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.

Composite material for EMI/EMP hardening protection in marine

An electromagnetically shielded connector assembly that enables connection rom any one of conduit and cable to any one of conduit, cable and ground plane irrespective of the particular sizes of the members to be connected.

Universal ground adapter assembly

An internal shield ground adapter uses spring contacts inside the kickpipe/stuffing tube to make a wideband, low impedance 360 degree contact between the shield of a cable passing through the kickpipe/stuffing tube and the kickpipe/stuffing tube itself. An environmental seal compresses the spring contacts against both the cable shield and kickpipe/stuffing tube while preventing degradation of the system by environmentally sealing the area between the cable and kickpipe/stuffing tube.

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Old Lyme, CT, United States of America

David S Dixon