Full Manufacturing Process of Conductive Shielding Foam: From Substrate Selection to Final Delivery

In EMI (Electromagnetic Interference) protection systems for modern electronics, conductive shielding foam plays a critical role as a sealing material. Its performance depends not only on the raw material itself but also on the entire manufacturing process. Based on “Conventional Foam Process Instruction.pdf”, this article systematically analyzes the complete production workflow of conductive shielding foam—from substrate selection to final delivery—helping engineers fully understand the process logic and technical essentials.

1. Substrate Selection: The Starting Point for Performance and Cost

The choice of substrate directly affects flexibility, temperature resistance, and environmental compliance. Common substrate types include:

1. Polyurethane (PU) Foam

• Advantages: Cost-effective, good elasticity, suitable for general EMI shielding

• Applications: Consumer electronics, industrial devices, automotive electronics

• Temperature range: -40℃ to 100℃ (up to 150℃ for high-temperature grades)

2. Silicone Rubber Foam

• Advantages: Excellent heat resistance, eco-friendly, RoHS/REACH compliant

• Applications: Outdoor telecom equipment, medical devices, high-temperature conditions

• Temperature range: -50℃ to 200℃ (depending on grade)

3. EPDM Foam

• Advantages: Excellent weather resistance, aging resistance, and waterproof performance

• Applications: Outdoor base stations, industrial control cabinets, high-humidity environments

• Features: Closed-cell structure, suitable for IP67 sealing requirements

👉 For more substrate comparisons, see How to Select the Right Type of Conductive Shielding Foam for Your Application?.

2. Metal Coating Processes: The Key to Conductivity

After substrate selection, conductive performance is achieved through metal coating. Common methods include:

1. Nickel-Copper (Ni-Cu) Coating

• Process: Electroplating + heat treatment

• Features: Surface resistivity ≤0.1Ω/sq, strong corrosion resistance, cost-effective

2. Silver-Copper (Ag-Cu) Coating

• Process: Chemical deposition + vacuum plating

• Features: Higher conductivity than Ni-Cu, shielding effectiveness up to 80dB, ideal for 5G/ mmWave devices, but higher cost

3. Nano-Silver Coating

• Process: Nano-spraying + curing

• Features: Ultra-thin design (<0.2mm), highly uniform, reduces signal reflection, optimized for wearables, relatively high cost

👉 For shielding effectiveness comparison, see Metal-Coated Conductive Foam: Advanced EMI Shielding Technology Explained.

3. Processing and Forming: From Rolls to Finished Products

1. Slitting Process

• Applications: High-volume, regular shapes

• Equipment: Precision slitters (±0.05mm tolerance)

• Output: Continuous rolls or sheets

• Advantage: High efficiency for standardized production

2. Die-Cutting Process

• Applications: Complex profiles, precision assemblies (e.g., irregular EMI shields)

• Technology: Laser die-cutting (0.1mm precision) or stamping dies

• Structures:

  • Single-layer conductive foam

  • Multi-layer composites (conductive foam + adhesive + release liner)

3. Hot-Press Forming

• Applications: 3D sealing (e.g., chassis corners, curved edges)

• Process essentials:

  • Mold temperature: 120–180℃

  • Uniform pressure to avoid deformation

  • Closed-cell structure ensures long-term compression recovery

4. Quality Control and Testing Standards

Physical Performance

• Compression rate: ASTM D3574 (40–70%)

• Recovery rate: ≥90% (silicone foam)

• Temperature resistance: -50℃ to 200℃ (depending on substrate)

Electrical Performance

• Surface resistivity: ASTM F390 (≤0.1Ω/sq)

• Shielding effectiveness: ASTM D4935-99 (65–80dB)

• Conductivity: Multimeter contact resistance verification

Environmental Compliance

• RoHS: Halogen-free, low VOC

• REACH: Hazardous substance screening

• UL certification: Flame-retardant grade (e.g., 94V-0)

5. Typical Applications and Process Adaptation

1. Industrial Control Panels

• Requirement: Long-term compression stability, abrasion resistance

• Process: EPDM + Ni-Cu coating + hot-melt adhesive

• Design: Snap-fit installation for easy maintenance

2. Automotive Camera Modules

• Requirement: Vibration resistance, IP68 sealing

• Process: Silicone substrate + Ag-Cu coating + closed-cell structure

• Testing: 500-hour salt spray test

3. 5G Base Station Antenna Housings

• Requirement: mmWave shielding, lightweight structure

• Process: Ultra-thin PU substrate + nano-silver coating + SMT integration

• Thickness tolerance: ±0.05mm

6. Konlida Process Advantages and Custom Services

With years of technical expertise, Konlida provides end-to-end conductive foam manufacturing services, including:

• Rapid prototyping: Samples within 72 hours

• Mass production: ISO 9001-certified lines, JIT delivery

• Eco-compliance: RoHS and REACH certified materials

• Flexible customization: Non-standard shapes, multi-layer composites, advanced coatings

Conclusion: Process Innovation Driving EMI Solutions

The manufacturing process of conductive shielding foam is the bridge between material performance and application reliability. Through precise substrate selection, advanced coating technologies, and high-precision forming, Konlida delivers high-reliability EMI shielding solutions that ensure stable performance in complex environments.