RFI and EMI - Contacts, Fingerstock and Gaskets

Image	Part Number	Description / PDF	Quantity	Rfq
	0097097501 Laird - Performance Materials	LS,STR,BF	0
	4797AB51K09600 Laird - Performance Materials	GK NICU NRS PU V0 KN	0
	8516-0123-89 Laird - Performance Materials	MIL CONNECTOR,ECE089 33.3X28.6X2	0
	0077001819 Laird - Performance Materials	SLMT,3F,NIB	0
	0097056017 Laird - Performance Materials	TWT,STR,SNB,PSA	0
	4358AB51K03600 Laird - Performance Materials	GK NICU NRS PU V0 DSH	0
	0098097517 Laird - Performance Materials	LS,STR,SNB,USFT,PSA	0
	0077001718 Laird - Performance Materials	SLMT,2F,NIE	0
	0098055005 Laird - Performance Materials	TWT,STR,CDY,USFT,PSA .030X.230X.	0
	0097032019 Laird - Performance Materials	CSTR,STR,NIB	0
	0095070051 Laird - Performance Materials	USBC,SS	0
	0077007115 Laird - Performance Materials	GASKET BECU 11.43X411.48MM	0
	3962001000 Laird - Performance Materials	FLX,STR,BF,PSA,CTL .170X.195X.18	0
	4675AB51K09600 Laird - Performance Materials	GK NICU NRS PU V0 REC	0
	0097095419 Laird - Performance Materials	S3,STR,NIB,PSA	0
	67B5G2007006215R00 Laird - Performance Materials	SP,CON,5,AU,TNR	0
	0098095519 Laird - Performance Materials	S3,STR,NIB,USFT,RIV	0
	0097063116 Laird - Performance Materials	CLO,STR,TLN,ZNY	0
	4E06AC51K00047 Laird - Performance Materials	GK NICU NRS PU V0 TRI	0
	4519PA51H01200 Laird - Performance Materials	GK NICU PTAFG PU V0 SQ	0

RFI and EMI - Contacts, Fingerstock and Gaskets

1. Overview

RF/IF (Radio Frequency/Intermediate Frequency) and RFID (Radio Frequency Identification) systems require effective electromagnetic interference (EMI) and radio frequency interference (RFI) shielding to maintain signal integrity. Contacts, fingerstock, and gaskets are critical components for ensuring electrical continuity and shielding performance in electronic enclosures. These components prevent electromagnetic leakage while maintaining mechanical functionality in connectors, housings, and assemblies.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Contacts	Conductive elements for maintaining electrical connections under compression	RF connectors, PCB grounding pads
Fingerstock	Resilient metal strips with finger-like projections for continuous shielding	Server chassis, military equipment
Gaskets	Conductive elastomers or mesh materials for sealing gaps	Automotive sensors, medical devices

3. Structure and Composition

Typical structures include:

Contacts: Beryllium copper or phosphor bronze cores with conductive platings (gold, silver, nickel)
Fingerstock: Canted coil springs or stamped metal fingers with corrosion-resistant coatings
Gaskets: Silicone rubber with embedded silver-aluminum particles or wire mesh

4. Key Technical Parameters

Parameter	Typical Range	Significance
Contact Resistance	0.1-10 m	Affects signal transmission efficiency
Shielding Effectiveness	60-120 dB (100 MHz-10 GHz)	Determines EMI/RFI attenuation
Compression Force	0.5-5 N/mm	Impacts mechanical durability
Temperature Range	-55 C to +150 C	Defines operational stability

5. Application Fields

Main industries include:

Telecommunications (5G base stations, microwave links)
Automotive (V2X communication systems, radar sensors)
Aerospace (avionics shielding compartments)
Medical (MRI shielding enclosures)

6. Leading Manufacturers and Products

Manufacturer	Representative Products
Parker Chomerics	CHO-SEAL conductive gaskets
Laird Performance Materials	Form-in-Place EMI gaskets
3M	EMI Shielding Tapes 9703/9706
Samtec	RFI/EMI shielded connectors

7. Selection Recommendations

Considerations include:

Frequency range of the application (higher frequencies require tighter tolerances)
Environmental conditions (temperature, humidity, chemical exposure)
Material compatibility (avoid galvanic corrosion between mating surfaces)
Cost-effectiveness (balance performance vs. budget constraints)

Case Study: In automotive radar systems, Parker Chomerics' silicone-based gaskets reduced EMI leakage by 40% compared to traditional metal fingerstock.

8. Industry Trends

Key development directions:

Miniaturization for 5G mmWave applications
Low-PIM (Passive Intermodulation) material formulations
Multi-functional integration with thermal management
RoHS-compliant plating processes (eliminating hexavalent chromium)