Thermalcote™ Thermal Grease

Thermalcote (Part #: 249, 250G, 251G, 252G, and 253G)

Thermalcote™ is a superior thermal joint compound of thermally-loaded silicone-based grease for use with all heat sinks. It improves the transfer of thermal energy across the metal-to-metal interfaces between the transistor or rectifier case and the heat sink.
Thermalcote conducts heat approximately 15 times better than air and more than 4 times better than unloaded silicone grease. It is non-toxic, extremely stable, and neither cakes nor runs from -40° to 204°C (-40°F to 399°F).

» MSDS Safety Sheet for Thermalcote in PDF format 41K

Thermalcote Resistance Calculator
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Color Opaque White
Temperature Range
-40°C to 204°C (-40°F to 399°F).
0.765Wm-1°C-1 (0.442 Btu/hr ft °F
strength 1.27 mm gap(0.050" gap)
11.8 x 103volts/mm (300volts/mil)
Mineral Spirits
or Turpentine
Specific gravity 1.6
Evaporation, 24 hours@200°C (392°F), wt% 1
Shelf Life
Indefinite1 (unopened)
One Year (opened)

(1) It is recommended that the containers be turned over every 6 months to minimize settling for ease of mixing.

Ordering Information

Part No. RoHS PCN Net Weight
249 28 grams (1 oz) tube
250G 57 grams (2 oz) tube
251G .45Kg. (1 lb) can
252G 2.27Kg. (5 lbs) can
253G 4.54Kg. (10 lbs) can

Thermalcote™II (discontinued)

Thermalcote™II (349G,350G,351G has been discontinued
Aavid Thermalloy can no longer supply Thermalcote™II product.
Please see our Sil-Free™ line of product instead.
Part No. PCN
No longer available
No longer available
No longer available
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