Thermal pads fill the air gap between a heat-generating device and a heat sink or metal base, and their flexible, resilient characteristics allow them to be used to cover very uneven surfaces. Heat is conducted from discrete components or the entire PCB to the metal enclosure or diffuser plate, increasing the efficiency and lifespan of heat-generating electronic components.
Advantages of thermal pads
1. The material is soft, the compression performance is good, the thermal conductivity and insulation performance are good, and the thickness can be adjusted in a relatively large range, suitable for filling the cavity, with natural viscosity on both sides, and strong operability and maintainability;
2. The main purpose of selecting the thermal pad is to reduce the contact thermal resistance between the surface of the heat source and the contact surface of the heat sink, and the thermally conductive silicone sheet can well fill the gap between the contact surfaces;
3. Since air is a poor conductor of heat, it will seriously hinder the transfer of heat between the contact surfaces, and installing a thermally conductive silicone sheet between the heat source and the radiator can squeeze the air out of the contact surface;
4. With the addition of thermal pads, the contact surface between the heat source and the radiator can be better and fully contacted, and face-to-face contact can be truly achieved. The temperature response can be as small as possible;
5. The thermal conductivity of the thermal pad is adjustable, and the thermal conductivity is better;
6. The process tolerance of the thermal pad in the structure is bridged, and the process tolerance requirements of the radiator and the heat dissipation structural parts are reduced;
7. The thermal pads has insulating properties (this feature needs to be added with suitable materials during production);
8. The thermal pads has the effect of shock absorption and sound absorption;
9. The thermal pads has the convenience of installation, testing and reusability.
Disadvantages of thermal pads
Compared with thermal grease, thermal pads have the following disadvantages:
1. Although the thermal conductivity is higher than that of thermally conductive silicone grease, the thermal resistance is also higher than that of thermally conductive silicone;
2. The thermal conductive silicone sheet with a thickness of less than 0.5mm has a complex process and relatively high thermal resistance;
3. The thermally conductive silicone grease has a larger temperature resistance range. They are thermally conductive silicone grease -60 °C ~ 300 °C, thermal conductive silicone sheet -50 °C ~ 220 °C;
4. Price: Thermal grease has been widely used, and the price is low. Thermal pads are mostly used in small and precise electronic products such as notebook computers, and the price is slightly higher.
