Laird Technologies has introduced its Sentry Form-in-Place conductive gasket materials. The new product line is replacing existing form-in-place conductive gasket materials. The new Sentry materials provide enhanced mechanical properties, increased adhesion to substrates and higher EMI shielding performance.
Sentry conductive gasket materials are one-part materals and include moisture cure (22 C and 50% relative humidity for 24 hours) and thermal cure (125 C for minimum 1 hour). Sentry conductive gasket materials are comprised of silicone with conductive metal filler, either silver plated aluminum, silver plated copper, silver plated nickel or low cost silver plated graphite. Generally, it is recommended to use filler with same material as substrate to minimize galvanic corrosion potential, i.e., use silver plated aluminum if applying the gasket onto an aluminum substrate.
The table below summarizes properties of new Sentry conductive gasket materials:
| Property | Units | SNL60-RXP | SNK55-RXP | SNN60-RXP |
|---|---|---|---|---|
| Elastomer | Silicone | Silicone | Silicone | |
| Filler | Silver Plated Aluminum | Silver Plated Copper | Silver Plated Nickel | |
| Volume Resistivity | ohm-cm | 0.003 | 0.002 | 0.005 |
| Shielding Effectiveness | dB | >100 | >90 | >100 |
| Hardness | Shore A | 60 | 55 | 60 |
| Tensile Strength | kPa | 850 | 1300 | 192 |
| Tensile Elongation | % | 140 | 300 | 110 |
| Compression Set | % | 10 | 10 | 15 |
| Adhesion to AL | N/cm2 | 140 | 200 | 180 |
| Compression Deflection | ||||
| at 20% Compression | lb/in | 1.9 | 1.2 | 1.7 |
| at 40% Compression | lb/in | 8.3 | 5.2 | 6.4 |
| Temperature Range | °C | -50 to +125 | -50 to +100 | -50 to +125 |
| Flammability Rating | UL94 | V0 | V0 | V0 |
EMI shield effectiveness over a broad frequency range provide designers with tools to control EMI emissions as well as mitigate cross talk between compartments of electronic devices. The table below provides EMI shielding for SNN60-RXP (silver plated nickel filled silicone) over frequencies from 100 MHz to 20 GHz:
Cybershield has available inventory of many of the Sentry Conductive gasket materials for customer sampling and evaluation. Contact us for more information.
