I. Overview
This is a high-performance specialty sealing gasket designed for demanding electromagnetic compatibility (EMC) and environmental protection requirements. It is not made from a single material but is a functional composite material precision-engineered by combining conductive silicone (elastic matrix), graphite (solid lubricant and conductive agent), and nickel powder (high-performance conductive filler). This unique combination gives it exceptional electrical conductivity, excellent environmental sealing, and reliable mechanical properties, making it an indispensable component in modern electronics.
II. Core Performance Characteristics
The performance of this composite gasket far exceeds that of ordinary rubber or metal gaskets. Its core advantages include:
- Excellent Electromagnetic Shielding Effectiveness (EMI Shielding)
- Mechanism: The nickel powder and graphite within the gasket form a dense three-dimensional conductive network. When electromagnetic waves radiate onto the gasket’s surface, this network effectively attenuates the electromagnetic energy through reflection and absorption mechanisms, converting it into minimal heat dissipation.
- Performance: Provides high shielding effectiveness, ranging from 60 dB to 120 dB, across a very wide frequency spectrum (from low to high frequencies). It effectively prevents internal electromagnetic interference (EMI) from leaking out of equipment and blocks external interference from entering, ensuring stable device operation.
- Stable Environmental Sealing
- Mechanism: The silicone base gives the gasket excellent compressibility and resilience. Even under compression and deformation, it tightly fills the gaps between two mating surfaces, forming an airtight and moisture-proof seal.
- Performance: Effectively prevents environmental pollutants such as dust, moisture, and salt spray from entering the equipment enclosure, providing protection levels up to IP67, IP68, or even higher, thereby extending equipment lifespan.
- Low Contact Resistance and High Conductivity
- Mechanism: The nickel powder provides high, metal-like electrical conductivity, while the flake graphite acts as a lubricant and fills micro-gaps between surfaces, ensuring more stable and numerous contact points.
- Performance: Establishes a low-resistance electrical path between two connecting components (e.g., metal enclosures, PCB ground planes), which is crucial for achieving good electrical grounding and signal reference.
- Good Mechanical Properties and Durability
- Low Compression Set: The silicone matrix ensures the gasket retains its shape well after prolonged compression, maintaining continuous shielding and sealing pressure, avoiding failure due to stress relaxation.
- High and Low Temperature Resistance: The silicone material inherently offers a broad operating temperature range (typically -55°C to +200°C), suitable for various harsh environments.
- Corrosion Resistance: The nickel-rich surface layer provides a degree of corrosion resistance, protecting the internal filler materials.
III. Primary Application Areas
This gasket is widely used in all electronic equipment and systems sensitive to electromagnetic interference and requiring environmental protection, including but not limited to:
- Aerospace and Defense: Radar systems, flight control units, communication and navigation equipment, electronic warfare systems, etc., which demand extremely high shielding reliability and environmental adaptability.
- High-End Communication Equipment: 5G base stations, microwave communication equipment, servers, routers, etc., needing to prevent signal cross-talk and ensure data integrity.
- Medical Electronics: MRI (Magnetic Resonance Imaging) machines, CT scanners, patient monitors, etc., where eliminating EMI is mandatory for patient safety and diagnostic accuracy.
- Automotive Electronics: Particularly in new energy vehicles for Battery Management Systems (BMS), infotainment systems, and shielding housings for autonomous driving sensors (radar, cameras).
- Industrial Electronics: Industrial PCs (IPCs), frequency converters, servo drives, etc., protecting precision control systems in industrially noisy EM environments.
IV. Core Functions
In practical applications, this composite gasket plays two vital roles:
- EMI Shielding Guardian: Its primary function is to eliminate electromagnetic leakage and interference. By creating a continuous conductive connection between two shielded components, it traps EM energy within or blocks it from entering the shielded cavity. It acts like a “Faraday cage” armor for precision electronic equipment, ensuring compliance with strict EMC regulations and enabling self-compatibility and coexistence with other devices.
- Environmental Sealing Barrier: Its other key function is to provide physical sealing. It protects internal expensive electronic components from erosion by environmental factors such as water, vapor, dust, and chemicals, preventing short circuits, oxidation, and corrosion, thereby significantly enhancing equipment reliability, stability, and service life.
V. Summary
The gasket made from a composite of conductive silicone, graphite, and nickel powder is a high-tech engineered product integrating conductivity, shielding, sealing, and elasticity. It successfully combines the excellent conductivity of metal with the superior elasticity and environmental adaptability of silicone, overcoming the drawbacks of poor resilience in traditional metal mesh gaskets and the limitations in shielding or strength of single-conductive rubbers. In today’s world of increasingly sophisticated electronic equipment and complex electromagnetic environments, it has become a key component ensuring reliable equipment operation and enhancing product quality.
Post time: Aug-28-2025