What is the thermal resistance of the thermal silica film?

Thermal conductivity is a parameter that can truly reflect the thermal conductivity of materials. It is an important parameter that corporate purchasers will first consult when purchasing. However, it is not enough to evaluate the thermal conductivity of thermally conductive silicone sheets under actual conditions. Because in addition to thermal conductivity is not enough, we need to consider the thermal resistance of the thermally conductive silicone sheet.

Thermal resistance refers to the ratio between the temperature difference between the two ends of the object and the power of the heat source when heat is transferred to the object. Its unit is Kelvin per watt (K/W) or Celsius per watt (°C/W). When heat flows through the interface of two solids in contact, the interface itself presents a significant thermal resistance to the heat flow, which is called contact thermal resistance.

Why do many thermal conductive materials say that they can effectively reduce the thermal resistance? The thermal resistance here refers to the contact thermal resistance, not the thermal resistance of the thermally conductive silicone sheet.First of all, we must have a conceptual diagram. The two look smooth and flat. For objects that are in good contact, the real contact is the part of the interface where the two are in contact. The other parts are gaps, and heat is transferred through the air in the gap, but its heat transfer ability is far less than that of ordinary solid materials, so it passes through the gap. Add a thermal silica gel sheet to remove the air as much as possible, and give proper pressure to make the surface close to the thermal silica sheet to reduce the contact thermal resistance.

thermally conductive silicone sheet.also has thermal resistance. It is not used for contact thermal resistance so that it can be observed in fact, but in fact it already has it. The heat is transferred through one end of the thermally conductive silicone sheet to the other end, and the process of transferring inside the thermally conductive silicone sheet It can be regarded as a person walking on flat ground. The thermal resistance is the obstacle on the flat ground, which hinders the speed of pedestrians. Therefore, the greater the thermal resistance of the thermally conductive silicone sheet, the lower the heat transfer efficiency through the thermally conductive silicone sheet, and the thermal conductivity is better. The worse.

The thermal resistance of a thermally conductive silicone sheet can directly affect its thermal conductivity. In addition to different thermal resistance values, the other parameters are the same, and the thermally conductive silicone sheet with less thermal resistance has better thermal conductivity.