EMI shielding gaskets are used to provide an electrically conductive seal for electronic equipment openings and housing covers to prevent or restrict electromagnetic interference. There are many types of EMI shielding materials and solutions available to the designer. Stockwell Elastomerics, Inc.'s EMI shielding materials are an extension of their silicone rubber capabilities - their EMI shielding gaskets are die cut, water jet cut or compression molded from electrically conductive silicone rubber compounds.

Conductive Silicone Rubber for EMI Shielding Gaskets
The main advantage of EMI shielding gaskets fabricated from conductive elastomers is the combined benefit of environmental sealing over a broad temperature range and EMI shielding. This EMI gasket material is typically silicone rubber or fluorosilicone rubber with embedded silver plated aluminum particles, silver plated glass beads, silver plated copper particles, nickel-graphite particles or conductive carbon. Many of these EMI shielding materials meet the properties of Mil-G-83528B. Conductive silicone rubber materials are typically molded into sheets from .010" to .125" thick and 12" x 12" to 10" x 15" in size and then die cut or water jet cut to the final gasket configuration. A partial listing of available compounds follows.

Compressible (softer) Conductive Nickel-Graphite Filled Silicone Gaskets
Rogers' EC2130 and EC2040 nickel-graphite filled silicone rubber is a compressible 30 and 40 durometer conductive gasketing material. Application of 3M #9713 conductive fabric supported acrylic adhesive provides both a conductive adhesive surface for EMI shielding integrity and dimensional stability to reduce tears during handling and assembly.

Prototype EMI Shielding Gaskets
Having in-house water jet cutting capability, Stockwell Elastomerics, Inc. is able to supply prototype gaskets from conductive compounds to enable your testing and final confirmation of the correct EMI shielding compound and configuration.

Molded EMI Shielding Gaskets
Stockwell Elastomerics, Inc. molds many of these conductive silicone rubber compounds in their in-house custom molding facility. Molded gaskets allow the designer to add sealing ribs and other performance enhancing features to optimize environmental sealing and EMI shielding properties. They have a broad range of compounds that meet Mil-G-83528B classifications for electrically conductive EMI shielding gaskets.

Oriented Wire in Silicone Rubber
Stockwell Elastomerics, Inc. has partnered with a supplier of silicone impregnated oriented mesh products to provide .030", .062" and .125" thick solid silicone rubber shielding products. These gasketing materials tend to be less costly than conductive silicone materials, with EMI properties provided by oriented Monel mesh (QQ-N-281) and Aluminum mesh (AMS-4182, alloy 5056).

Conductive adhesive backings
Stockwell Elastomerics, Inc. applies conductive metal fiber filled acrylic adhesive backings to many conductive EMI gasket materials.