How does thermal resistance affect the thermal conductivity of materials?

The heat-conducting material can effectively fill the gap between the heat-dissipating device and the heat-generating device, remove the air between the gaps, reduce the contact thermal resistance between the two, and improve the heat transfer efficiency, thereby enhancing the thermal conductivity. There are many kinds of thermally conductive materials on the market, such as thermally conductive silicone sheet, thermally conductive phase change film, thermally conductive gel, thermally conductive paste, thermally conductive silicone cloth, non-silicon thermally conductive sheet, etc., each thermally conductive material has its own characteristics and application Fields play their important role.

Companies or individuals often pay attention to their thermal conductivity when choosing thermal conductivity materials. There is a saying in the industry: purchase depends on thermal conductivity, and engineering depends on thermal resistance. Thermal conductivity is a subjective parameter that measures the thermal conductivity of a material. Whether the thermal conductivity of a thermally conductive material is good or not, the thermal conductivity can be seen. The higher the thermal conductivity of the thermally conductive material, the better the thermal conductivity, but it is not absolute, and the thermal resistance is large. The degree determines the thermal conductivity of the material. For example, the thermal conductivity of the two thermally conductive silicone sheets with the same other parameters except for the different thermal resistance, and the thermally conductive silicone sheet with lower thermal resistance will have better thermal conductivity. So how does thermal resistance affect thermal conductivity?

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 transmitted on the object. If it simply means that when the heat enters one end of the thermally conductive material, it is like a cyclist starting from the starting point. Starting to the finish line, if the road is smooth and unobstructed, the cyclist can move quickly to the finish line, but if the road is full of potholes or various obstacles, the athlete will slow down to pay attention to the road conditions, and the thermal resistance is equal to the road. The higher the obstacles, the more obstacles, the slower the speed, so why say that thermally conductive materials with low thermal resistance have better thermal conductivity.