High
technology composite EMI/RFI shielding materials that give design engineers
a choice
This premium grade conductive silicone
gasketing material contains a uniform dispersion of microscopic conductive
particles. It will withstand the most severe environments without degradation
of electrical or physical performance over a frequency range of 10 kHz to 12.4
GHz.
Designed For Exacting
Requirements These materials are produced in a uniquely wide
choice of conductive particles and silicone elastomers ranging in hardness from
40 to 80 Shore A durometer. As a result, the design engineer has maximum
freedom in selecting the material that provides the best combination of
shielding effectiveness, environmental protection and economy for his specific
application.
Conductive Particles For All
Environments A significant
design characteristic engineers must evaluate when
selecting a conductive compound is the environment
in which it will operate. This gasketing
is available with a selection of conductive particles to meet varying
performance requirements at operating temperatures to 200°C and beyond.
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SP
(pure
silver particles) provides the best
performance at temperatures to 200°C. Shielding effectiveness in excess of
70 db is possible with this material. |
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SPN
(silver
plated nickel particles) provides performance
which compares favorably with pure silver
compounds, also to 200°C, and is suitable for
similar applications. |
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SPC
(silver plated copper
particles) is a 135°C material which offers excellent performance. It is
intended for retrofit applications where similar silver plated copper materials
have been specified and qualified.
SPA gasketing material
(see hyperlink : SPA) uses plated aluminum particles in a specially
formulated silicone elastomer. This
material exhibits exceptional environmental,
electrical and physical characteristics.
It is similar in performance to our
top-of-the-line SPC but contains less silver. |
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SPG (silver plated inert particles) is intended for applications where
the cost of silver or silver plated metal fillers is prohibitive but silver
performance is required. The material is rated for 180°C operation where
greater than 60 db of shielding is required. |
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NP (nickel particles) is a 200°C, full frequency range material
which will provide 45 db of shielding effectiveness. It is not affected by salt
spray environments as the silver compounds are. |
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CP (carbon particles) is recommended for use below 5 GHz in
non-military applications. Where it meets performance requirements, its low
cost makes it attractive. |
Gasket Selection Guide
The Shielding Express
gasket selection guide
provides a more complete list of specifications for
the various conductive compounds identified above
and includes instructions on how to order various
gasket types..
Environmental Sealing
Shielding Express elastomers provide
complete environmental sealing. The wide range of elastomer durometers assures
an effective seal even where there is large unevenness between the mating
surfaces. Compression set is minimal. Fluorosilicone compounds are available
for applications involving contact with chemical solutions, organic or
inorganic oils or fluids.
Salt Corrosion Resistant Compounds Where the shielding
material must operate in a salt spray environment,
design engineers can eliminate problems caused by
the corrosive effect of salt spray on silvered
particles by specifying NP.
Fully Bonded Gasketing In some applications, improved design integrity is achieved by fully
bonding the gasketing directly to the parts by a vulcanizing process.
Vulcanizing, in which Shielding Express essentially forms gaskets in place by
permanently heat bonding directly to one of the mating surfaces, further
assures repetitive quality in limited space areas where conductive adhesives
would normally be used.
Product Configurations For All Applications
As shown in the photos
above, Shielding Express
gasketing is available in sheets, extruded strips
and molded or rule die cut parts. A wide range of
sizes, thicknesses and configurations can be
provided to meet specific design needs. Materials
are available with pressure sensitive adhesive
(PSA) backings for ease of installation. Please call
Shielding Express Inc. or write to
tech-info@shielding.com to specify the material
that best suites your environmental and shielding
effectiveness requirements.
Waveguide Gasketing Waveguide gaskets
are available in a wide range of EIA sizes as well as in special
configurations. They provide shielding effectiveness in excess of 75 db through
a frequency of 12.4 GHz and are usable to 26.5 GHz and beyond. Flat
waveguide gaskets are reinforced internally with a metal screen that prevents
cold flowing under high compression loads. Typical applications include cover
flanges and flat contact flanges. Molded waveguide gaskets are produced in
precise shapes of a rectangular or circular configuration with "O" or "D" cross
sections. Typical uses are as gasketing for choke flanges and grooved contact
flanges.
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