RFI and EMI - Contacts, Fingerstock and Gaskets

Part Number	Description / PDF	Quantity
0097014302 Laird - Performance Materials	CSTR,FRG,BF	0
4184PA51H09600 Laird - Performance Materials	GK NICU PTAFG PU V0 DSH	0
67B8G3004005108R00 Laird - Performance Materials	SP,CON,8,AU,TNR	0
4219AB51K03600 Laird - Performance Materials	GK NICU NRS PU V0 REC	0
4205AF51K03600 Laird - Performance Materials	GK NICU NRS PU V0 KN	0
4064PA51G09600 Laird - Performance Materials	GK NICU NRSG PU V0 REC	0
0098095115 Laird - Performance Materials	S3,STR,ZNC,USFT,PSA	0
4692PA51G00900 Laird - Performance Materials	GK NICU NRSG PU V0 DSH	0
4529PAH1K01475 Laird - Performance Materials	GK NICU NRS PU V0 CSH	0
4797AB51K06300 Laird - Performance Materials	GK NICU NRS PU V0 KN	0
0097054408 Laird - Performance Materials	AP,STR,SNSAT,RA	0
0097054117 Laird - Performance Materials	NOSG,STR,SNB,PSA	0
4980PA51H01200 Laird - Performance Materials	GK NICU PTAFG PU V0 SQ	0
8560-0630-93 Laird - Performance Materials	DIECUT ECE093 PSA	0
4695PA51H01125 Laird - Performance Materials	GK NICU PTAFG PU V0 SQ	0
4795AB22103937 Laird - Performance Materials	GK,NICU,PTAF,TPE,HB,REC .250X.50	0
0097082700 Laird - Performance Materials	DCON,25P,BF	0
4E06AD51K00154 Laird - Performance Materials	GK NICU NRS PU V0 TRI	0
4570PA01H01677 Laird - Performance Materials	GK,NICU,PTAFG,NF,V0,REC .015X.20	150
8865-0130-72 Laird - Performance Materials	DSTRSD,CUSTMATL 3.1X3.43X1.55MM	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)