Because the thermal silica gel is a thermal compound, the characteristics of not conducting electricity can avoid risks such as short circuit; Its high bonding performance and superior thermal conductivity are currently the best thermal conductivity solution when the CPU, GPU and heat sink are in contact. Therefore, it also has relevant performance parameters that reflect its own working characteristics. As long as we understand the meaning of these parameters, we can judge the performance of a thermal silica gel.
Heat conduction coefficient: the heat conduction coefficient of thermal silica gel is basically the same as that of the radiator, its unit is W/mK, that is, the heat conduction power when the temperature difference of the column with a cross-sectional area of 1 square meters is 1 Kelvin (1K = 1℃) along the axial distance. The larger the value, the faster the heat transfer speed of the thermal conductive silica gel, the better the thermal conductivity. At present, the thermal conductivity of mainstream thermal silica gel is greater than 1.0W/mK.
Thermal resistance coefficient: The thermal resistance coefficient indicates the obstruction effect of the object on heat conduction. The concept of thermal resistance is very similar to resistance, and the unit is similar to it (° C /W), that is, the temperature difference between the two ends of the thermal conductivity path when the object's continuous heat transfer power is 1W. The lower the thermal resistance is obviously the better, because under the same ambient temperature and thermal conductivity power, the lower the thermal resistance, the lower the temperature of the heating object. The size of the thermal resistance has a great relationship with the material used in the thermal conductive silica gel.
Working temperature: The working temperature is an important parameter to ensure that the thermal silica gel is in a solid or liquid state. If the temperature is too high, the thermal silica gel will be converted into a liquid. If the temperature is too low, it will become solid due to the increase in viscosity, both of which are not conducive to heat dissipation. The working temperature of thermal silica gel is generally -50 ° C ~ 180 ° C.
Dielectric constant: For some cpus without metal cover protection, the dielectric constant is a very important parameter, which is related to the problem of whether there is a short circuit inside the computer. Thermal conductive silica gel is used in good insulation materials, to avoid the occurrence of conductive phenomena like silver-containing thermal conductive silicone grease.
Voltage resistance: thermal conductive silica gel has insulation and thermal conductivity characteristics because of its own material characteristics, and has good protection for IC, because thermal conductive silica gel curing is not easy to be pierced and torn or damaged under pressure, the reliability of voltage resistance is better.
Viscosity: Viscosity refers to the viscosity of the hot silica gel. In general, the viscosity of thermal silica gel is about 68.