Thermal Interface Materials and Thermal Resistance

Heat is generated during the use of electrical equipment, but it is unavoidable because heat is generated when the current passes through the resistance. The internal space of the device is small, which makes it difficult for the heat to dissipate to the outside. Therefore, it is necessary to install a heat sink on the surface of the heat source, and guide the heat from the surface of the heat source to the heat sink through the contact between the heat source and the heat sink, thereby reducing the temperature of the heat source.

In reality, two solid surfaces in contact with each other, the actual contact between the two is some discrete areas, and the other non-contact interfaces are filled with air, and the heat will be subjected to additional resistance when passing through, which is called the contact thermal resistance, and the contact between the two is The greater the thermal resistance, the higher the resistance to the heat passing through, so the role of the thermal interface material is to effectively reduce the contact thermal resistance, so that the heat can be quickly transferred to the heat sink.

There must be gaps between the surfaces. The thermal interface material fills the contact interface, reduces the contact thermal resistance, and removes the air in the gap, thereby improving the heat transfer efficiency. There are many types of tthermal interface material, which are different in different materials and application environments. choice, but they mainly improve the cooling effect of the device, so as to ensure that the device will not be damaged by high temperature.