2025 SMT Gasket Selection Guide: Structure, Performance & Applications
What Is an SMT Gasket?
An SMT Gasket (Surface-Mount Conductive Gasket) is a PCB-level conductive elastic terminal designed for high-density electronics. It typically consists of a silicone or foamed silicone core wrapped with a conductive PI layer, enabling stable electrical grounding and mechanical cushioning in compact devices.
Core Advantages
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Strong EMI/ESD shielding — Provides a low-impedance grounding path for suppressing high-frequency interference.
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SMT reflow compatible — Supports standard 260°C reflow soldering for automated assembly.
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Excellent buffering performance — Absorbs impact energy and protects delicate modules.
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High reliability — Qualified through salt spray, humidity, and thermal shock testing.
Typical Use Cases
Smartphones, notebooks, antennas, PCB-to-FPC grounding, module shielding, and connector replacement.
👉 Related reading:
What Is Conductive Foam?
https://www.konlidainc.com/whaticle.html
Three Main Structure Types (with Comparison)
SMT Gaskets differ mainly in the design of the silicone core and the conductive wrapping layer. According to Konlida’s engineering data, the three mainstream structures include:
| Structure Type | Description | Key Advantages | Limitations | Recommended Applications |
|---|---|---|---|---|
| Conductive PI-Wrapped Extruded Silicone Foam | Extruded foamed silicone wrapped with conductive PI film | - Strong anti-tilt stability - Flexible custom geometry |
- Silicone expansion at high temp - Larger thickness tolerance |
Custom designs requiring high compression stability |
| Conductive PI-Wrapped Open-Cell Silicone Foam | Modified open-cell silicone foam with PI wrap | - High compression range & low force - Wear-resistant & stable - Ideal for small sizes (1–2 mm) |
Slightly lower rebound force | TWS earbuds, compact modules requiring high compression travel |
| Conductive PI-Wrapped Solid Silicone Foam | Solid silicone foam wrapped with PI | - Cost-effective - Can use adhesive (no soldering required) |
- Lower dimensional precision - Thermal expansion risk |
Non-critical, cost-sensitive EMI grounding |
👉 Further reading:
Fabric over Foam Gaskets: Performance Analysis
https://www.konlidainc.com/fof.html
Key Performance Indicators (Based on Konlida Test Data)
Correct SMT Gasket selection requires evaluating electrical, mechanical, and environmental parameters.
Electrical Properties
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Surface resistance: ≤ 0.05 Ω/inch (ASTM F390)
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Vertical resistance: ≤ 0.03 Ω/inch (DS/EN 1149-2)
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Contact impedance: ≤ 0.03 Ω
Mechanical Properties
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Recommended compression: 10–40%
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Rebound rate: ≥ 90% (Konlida test: 94.8% after 168 hours)
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Compression set: ≤ 32% (70 h @ 100°C)
Environmental Reliability
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Reflow compatible: 260°C
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Operating temperature: –40°C to +150°C
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Salt spray test: 24h with no resistance degradation
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Compliance: RoHS, halogen-free (IEC 62321)
Physical Specifications
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Minimum size: 1.5 mm × 1.0 mm
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Thickness: From 0.3 mm for ultra-thin designs
New Challenges in the 5G Era & Konlida’s Innovations
5G devices require higher shielding effectiveness, wider frequency bands, lower thickness, and better thermal conductivity.
Konlida’s response:
1. Advanced Material Development
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High-temperature conductive PI film (up to 300°C)
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Conductive fiberglass fabrics for enhanced structural strength
2. Structural Innovation
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LOOP-structure conductive foam for reduced weight, lower profile, and internal circuit connectivity.
3. Functional Hybrid Materials
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Magnetic nanoparticle-enhanced SMT Gaskets
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Combined shielding + absorption for eliminating harmonic interference
👉 Related technical insights:
Breaking the EMI Failure Curse: Impedance Control Innovations
https://www.konlidainc.com/article/foam.html
Why Choose Konlida for SMT Gaskets?
1. Full In-House Manufacturing
From conductive PI film to silicone extrusion, forming, and carrier-tape packaging—Konlida controls the entire supply chain for consistent quality and competitive cost.
2. Flexible Customization
Supports large-scale stable supply and quick delivery for small-batch custom models.
Samples in as fast as 2 days (when materials are available).
3. Strict Quality System
Certified by ISO9001 and IATF16949, with complete incoming inspection, process monitoring, and final testing.
4. Trusted by Global Brands
Long-term partner of leading international electronics companies, delivering high-reliability EMI shielding components.
Need an SMT Gasket Solution?
Konlida provides free sample evaluations, application analysis, and professional EMI design support.
Suzhou Konlida Precision Electronics Co., Ltd
Website: www.konlidainc.com
Email: sales78@konlidacn.com
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