Silicone grease

Silicone grease is a waterproof grease made by combining a silicone oil with a thickener. Most commonly, the silicone oil is polydimethylsiloxane and the thickener is amorphous fumed silica. Using this formulation, silicone grease is a translucent white viscous paste, with exact properties dependent on the type and proportion of the components.

It is commonly used for lubricating and preserving rubber parts, such as O-rings, as it prevents the rubber from drying out. In addition, silicone grease will not swell or soften the rubber, which can be a problem with hydrocarbon based greases. It functions well as a corrosion-inhibitor and lubricant for purposes that require a thicker lubricant, such as the operating mechanism of the M1 Garand rifle.

The most common use of it is an elastic heat transfer coupling material between semiconductor circuit elements and cooling metal parts attached to them. This way thermal resistance of touching surfaces is typically lowered by 50 percent. Wide temperature range stability enables it to do its job even on the extreme hot, cold and wet surfaces of peltier elements.

Silicone grease is also used widely by the plumbing industry in faucets and seals, as well as dental equipment. Electrical utilities use silicone grease to lube separable elbows on lines which must endure high temperatures. Silicone greases generally have a temperature range of -40C to 400C.