Small Silicone Grease Big Role, Heat Conduction And Lubrication You Use Right?

Often we see that because you can't tell the difference between thermal conductive silicone grease and smooth silicone grease, you don't know how to use it after buying silicone grease. Maybe Zhang Guanli Dai used the wrong silicone grease and made some ironic things. As a hardware enthusiast who has been burning for several years, I have some knowledge of silicone grease. Let me give you a brief introduction to this small "silicone grease".

Two types of "silicone grease" are used in our telephones, the thermal conductive silicone grease between the LED substrate and the copper bin, and the smooth waterproof silicone grease with O-ring threads.

Handle the definitions of two types of "silicone grease":

Thermal conductive silicone grease is a kind of heat conductive paste. It refers to the thermal conductive silicone grease compound made from silicone ketone (that is, silicone oil) as the main raw material, with the addition of excellent heat resistance and thermal conductivity. Because even the two planes with very bright appearance will appear in space when they contact each other, the air in these spaces is a bad conductor of heat, which will hinder the heat transfer to the radiator. Thermal conductive silicone grease can fill these spaces, make the heat transfer more smoothly and rapidly, thereby improving the heat dissipation power. Additional thermal conductivity data include alumina, aluminium nitride, zinc oxide, silver compounds, etc.

Smooth silicone grease (i.e. silicone-based smoothing grease) is a white organic silicone grease refined from modified silicone oil with excellent properties at high and low temperatures, special lithium soap as thickener and with white solid smoothing agent, anti-oxidation, anti-corrosion and other additives. White solid smoothing agent generally refers to PTFE (Teflon 4) as the primary smoothing and waterproof effect in mobile phones.

Simply put, the thermal conductive silicone grease is mainly silicone oil + thermal conductivity data, and the silicone-based smooth grease is mainly silicone oil + solid smooth agent. Although they have the same matrix, their uses are quite different. One is heat conduction, the other is smooth. What determines their different properties is the different fillers added.

The cheapest thermal conductive silicone grease on the market is the silicone grease added with alumina, commonly known as white silicone grease, which is the slag with heat conductivity of only 1W/mK. The thermal conductivity of 7783 silver-containing silicone grease is 6W/mK, and the thermal conductivity of 7783 silicone grease with high-quality thermal conductivity data can reach more than 10W/mK. The thermal conductivity of 7783 silicone grease is more than 10 times that of White Silicone grease.

Teflon added with silicon-based grease has the smallest friction coefficient in plastics. It feels slippery than ice surface. It is also insulated, wear resistant, high and low temperature resistant and corrosion resistant. It is a very high quality smooth material. Adding Teflon silicone grease is more slippery than pure silicone oil, which is greasy and not easy to lose. It is often used as medium and high temperature smoothing agent.

So can they work? No!

Because fillers, such as metal compounds, which play an important role in conducting heat in silicone grease, have relatively large particles. Converted to the number of meshes, they are about 1000-4000. They have high friction coefficient and feel rough. The filler particles have edges and corners, and have high hardness (e.g. alumina is 8.8, which can scratch stainless steel), which can wear threads. The heat conductive silicone grease will dry and solidify over a long period of time, and become gypsum solid to adhere to the flashlight.

Thermal conductive silicone grease is mainly designed for electronic equipment. Except for adding graphite powder and silver powder, it is basically insulated. If the threaded conductive flashlight is used, the resistance will increase sharply and the brightness will decrease. Thermal conductive silicone base is not suitable for thread smoothing. The Teflon heat conductivity of silicone grease is only 0.25W/mK, which is lower than that of White Silicone grease, so it is not suitable for thermal conductivity.