Heat Sink Silicone Lubricating Compound

PST-540 is a thermally-conductive, medium-bodied, heat sink silicone compound for applications that require excellent heat transfer. This product was formerly known as SSP-1405-L and is now a PolySi® G-MAN® silicone lubricating compound.

Data Typical Values
Appearance White/Transparent
Temperature −65°F to 400°F
Worked Penetration (260 – 320 Range) 290
Unworked Penetration (Report) 275
Bleed (1.0% max) 0.1% after 1 hour @ 200°C
Evaporation (1.5% max) 0.5% after 1 hour @ 200°C
Specific Gravity (2.3 – 2.4 range) 2.4
Hegman Grind (Report) 3.5

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Heat Sink Silicone Lubricating Compound

PST-540 is a thermally-conductive silicone grease that’s designed for demanding applications that require excellent heat transfer. This medium-bodied, heat sink compound is comparable to Dow Corning Molykote 340 thermally-conductive grease (DC-340) and to Novagard G641 heat sink grease lubricant.

PST-540 Silicone Grease Features

PST-540 has an operating temperature range of −65°F to 400°F and an unworked penetration in the 260 to 320 range with a typical value of 275. This silicone grease is chemically inert, water-resistant, and hydrolytically stable. PST-540 combines excellent dielectric properties with low bleed and evaporation and does not dry out, harden, or melt.

PST-540 Silicone Grease Applications

PST-540 silicone lubricating grease is used with mounting studs for transistors and diodes, thermocouple wells, and thermal joints. Applications include mica chips, thermal couples and thermometer wells, shock, and heat dissipation in transistors. With its excellent dispersion and stability, PST-540 is also used in mounting semi-conductive devices, automotive voltage regulators, distributors and ignition modules, and as a heat transfer medium and ballast.

PST-540 Packaging and Product Specifications

PST-540 silicone lubricating grease is supplied in drums, plastic pails, jars, cartridges, and tubes. Private labeling and custom packaging are available to meet special requirements. Contact PolySi Technologies for more information.