For applications that demand both thermal conductivity and proven reliability in demanding environments, Parker Chomerics CHO-THERM 1678 delivers a compelling package. It is a pink silicone fiberglass pad rated at 2.0 W per meter-Kelvin with strong dielectric properties and a recognized UL 94 V-0 flammability rating. At NEDC, we convert 1678 for telecom, industrial control, and aerospace customers who need thermal performance backed by decades of field history.
Key Specifications
- Material: Silicone with fiberglass reinforcement
- Thickness: 0.010 in (0.25 mm) with plus or minus 0.002 in tolerance
- Color: Pink
- Thermal Conductivity: 2.0 W per meter-Kelvin (ASTM D5470)
- Thermal Impedance at 300 psi: 0.20 degrees C-inch squared per watt
- Voltage Breakdown Dry: 2,500 Vac per mil (100 kVac per mm, ASTM D149)
- Volume Resistivity Dry: 10 to the 14 power ohm-cm
- Dielectric Constant at 1,000 kHz: 3.6 (ASTM D150)
- Dissipation Factor at 1,000 kHz: 0.007
- Tensile Strength: 3,000 psi (20.7 MPa, ASTM D412)
- Tear Strength: 200 lb per in (35 kN/m, ASTM D642)
- Elongation: 20 percent (ASTM D412)
- Hardness: Shore A 80 (ASTM D2240)
- Specific Gravity: 1.55 (ASTM D792)
- Flammability: UL 94 V-0
- RoHS Compliant: Yes
- Operating Temperature: minus 76 to 392 degrees F (minus 60 to 200 degrees C)
- Shelf Life: Indefinite (dry); 18 months (with PSA)
- Outgassing: 0.55 percent TML, 0.12 percent CVCM (ASTM E595)
Why Specify CHO-THERM 1678?
1678 is positioned as a high-performance grade in the original CHO-THERM product line. It offers excellent thermal properties, a recognized V-0 rating, and proven field history in military and aerospace applications where reliability is non-negotiable. The low outgassing numbers make it appropriate for clean environments, while the familiar silicone fiberglass construction ensures compatible handling with standard die-cutting equipment and assembly methods.
Typical Applications
- Power semiconductors and telecommunications gear
- Industrial control modules
- Military and aerospace power systems
- Motor and engine controllers where low outgassing is specified
NEDC converts CHO-THERM 1678 into die-cut parts, sheets, and rolls. Compare with T500 for similar high-performance, 1671 for the top CHO-THERM conductivity, or 1674 for a more economical option.