Signal Leakage Control
Conductive filler or conductive surfaces create a shielding path across structural gaps when the gasket is compressed.
Custom EMI Gaskets
Fecision manufactures custom EMI shielding gasket solutions for electronic enclosures, connector interfaces and housing joints that need electromagnetic shielding continuity.
- Conductive silicone, fluorosilicone, EPDM, fabric-over-foam available
- Process include die-cut, extrusion, bonding, and molding
- Design review and 1-to 1 engineer support
What Is An EMI Gasket?
An EMI gasket is a conductive sealing part used to close electrical gaps in an enclosure shielding system.
EMI gaskets are used around openings, doors, seams, connector interfaces, and enclosure joints to help keep unwanted electromagnetic signals from entering or leaving an electronic device.
An EMI gasket must maintain electrical contact between mating surfaces. Depending on the design, it may also need to keep out dust and water while the enclosure vibrates or is opened for maintenance.
Conductive silicone and conductive fluorosilicone are common choices because they combine elastomeric sealing with conductive fillers such as silver, aluminum, nickel, copper, carbon, or nickel-graphite.
EMI/RFI Shielding
How EMI Gaskets Support Enclosure Shielding
EMI means electromagnetic interference. RFI means radio-frequency interference, which is a type of EMI within the radio-frequency range. In practical gasket design, both are reviewed together because the shielding result depends on frequency, enclosure design, contact pressure, and surface conductivity.
The gasket forms only one part of the shielding path. It needs good contact with the housing and a continuous route to ground. Poor contact at a joint or fastener can reduce the performance of the complete enclosure.
Grounding Continuity
Material choice, plating, fastener spacing, and compression load must work together to maintain electrical contact.
Environmental Sealing
The same EMI gasket can also help resist dust, splash, weather, vibration, and enclosure movement when the material and profile are selected correctly.
Common EMI Gasket Materials
The base material controls flexibility, compression behavior, temperature resistance, and environmental sealing. Conductive fillers or conductive surfaces create the shielding path.
Conductive Silicone
Conductive silicone is flexible, easy to mold, easy to die cut, and stable across a broad temperature range. It is useful when the gasket also needs compression recovery, softness, and sealing against dust or light moisture.
Best for: Electronic devices, connector interfaces, access panels, and general EMI shielding gaskets.
Conductive Fluorosilicone
Conductive fluorosilicone keeps much of silicone's flexibility while improving resistance to fuels, oils, and harsh fluids. It is often selected when EMI shielding and fluid exposure appear in the same design.
Best for: Aerospace, defense, automotive, and demanding connector sealing environments.
Conductive EPDM
EPDM is known for weather, ozone, water, and outdoor aging resistance. When EMI shielding is needed in outdoor but oil-free service, EPDM-based shielding materials may be worth reviewing.
Best for: Outdoor enclosures, water-facing designs, and weather-exposed equipment.
Fabric Over Foam
Fabric-over-foam gaskets use a soft foam core covered with conductive fabric or mesh. This structure supports low closure force for light doors, covers, and access panels.
Best for: Low-force closures, light covers, and assemblies where strong environmental sealing is not the main requirement.
Beryllium Copper
Beryllium copper is a spring metal used in EMI fingers, clips, and contact strips. It can provide strong electrical contact over many opening and closing cycles.
Best for: Spring contact, repeated cycling, and designs where soft elastomer sealing is less important.
Material review
Need Help Choosing An EMI Gasket Material?
Send the enclosure drawing, mating metal, compression space, shielding target, fluid exposure, and production volume. Fecision can help compare conductive silicone, fluorosilicone, EPDM, fabric-over-foam, or metal contact options.
Request Material ReviewEMI Gasket Manufacturing Processes
The best production route depends on gasket shape, material, volume, shielding target, and assembly method.
CNC Cutting
Best for prototypes, small batches, and fast design checks when the enclosure interface is still changing.
- No hard tooling investment before the EMI gasket design is confirmed
- Useful for early material comparison, fit checks, and low-volume builds
Die Cutting
Best for flat EMI gaskets that need repeatable holes, slots, adhesive backing, and medium-to-high volume output.
- Supports PSA backing, kiss-cut liners, bolt holes, and nested layouts
- Works well with conductive silicone sheet, fluorosilicone sheet, foam, and fabric-over-foam
Extrusion
Best for long enclosure seams, flange seals, groove seals, and continuous shielding profiles.
- Common profiles include solid O, hollow O, D, P, E, U, square, and hollow square
- Splicing and bonding can create closed EMI shielding loops for doors and covers
Compression Molding
Best for three-dimensional EMI gaskets with molded ribs, bosses, alignment features, and local sealing details.
- Creates controlled contact paths when the gasket is not flat or cannot be die cut
- Can reduce scrap when conductive compounds are expensive and geometry is complex
Design Considerations For Custom EMI Gaskets
Material selection is only one part of the design. The gasket must maintain reliable electrical contact after assembly while meeting the mechanical and environmental requirements of the enclosure.
Shielding Target
Define the frequency range and required shielding effectiveness before material selection.
Compression Load
Make sure the enclosure can compress the gasket enough to create contact without damaging the part.
Height And Compression Range
Review gasket height carefully to avoid under-compression, over-compression, and contact loss.
Surface Plating
Match conductive fillers to the mating metal surface to reduce galvanic corrosion risk.
Environmental Sealing
Decide whether the gasket must also block water, dust, oils, fuels, or cleaning agents.
Attachment Method
Choose groove retention, mechanical fastening, PSA backing, or molded-in features around the assembly process.
Service Life
Check compression set, aging, vibration, abrasion, and opening cycles for the real use case.
Production Route
Match the process to geometry, tolerance, volume, tooling budget, and conductive material cost.
EMI Gasket Applications
EMI shielding is no longer limited to defense or radio systems. It is now used across compact electronic products, connected devices, medical systems, industrial controls, and harsh-environment equipment.
Communication
Cellular networks, Wi-Fi systems, antennas, base stations, RF modules, and shielded enclosures can use EMI gaskets to reduce signal leakage and interference.
Defense And Aerospace
Satellite systems, GPS devices, radar units, aircraft electronics, and communication hardware need stable shielding through vibration, temperature cycling, and harsh environments.
Medical Devices
Ventilators, infusion pumps, patient telemetry, imaging systems, and wearable devices may need shielding reviewed together with cleaning, enclosure design, and regulatory needs.
Automotive
Control units, sensors, power electronics, connected modules, and battery-related assemblies can require both electrical shielding and environmental sealing.
Fecision Custom EMI Gasket Support
Fecision supports custom EMI gasket projects that need more than a standard flat seal.
For molded EMI gaskets, the material choice usually starts with conductive silicone rubber or conductive fluorosilicone. Our silicone rubber molding service can support molded ribs, bosses, alignment tabs, sealing details, and complex contact paths.
We can finish the gasket and prepare it for assembly in-house. Any bonding or splicing steps are defined during design review, along with the required inspection and packaging records.
- Material and filler review around shielding, compression, and galvanic compatibility
- DFM feedback for gasket height, compression range, ribs, bosses, and sealing contact
- Die-cut, extruded, spliced, bonded, and compression-molded EMI gasket production routes
- Inspection support for dimensions, appearance, contact surface, packaging, and shipment needs
Need A Custom EMI Gasket For Your Enclosure?
Send your drawing, material target and expected production volume. Fecision can help review the EMI gasket material and manufacturing route.