Thermal pads are designed to facilitate the transfer of heat between two surfaces, such as a heat-generating component and a heat sink. They are made of a soft, compliant material with high thermal conductivity. The primary purpose of a thermal pad is to fill the gaps and imperfections between two surfaces, ensuring efficient heat transfer and minimizing the risk of air pockets that could hinder thermal dissipation.
Here's how thermal pads work:
Contact and Compression: When a thermal pad is placed between two surfaces, such as a CPU and a heatsink, it forms a direct contact layer. When pressure is applied, either through screws or mounting mechanisms, the thermal pad gets compressed. The compression helps to eliminate any air gaps and conform to the surfaces' irregularities, creating a better thermal interface.
Conduction: The thermal pad material has high thermal conductivity, meaning it can efficiently transfer heat from one surface to another. As the heat-generating component operates, it produces thermal energy that is conducted through the thermal pad to the heat sink or another cooling solution.
Thermal Resistance: While thermal pads are effective in transferring heat, they do introduce some thermal resistance due to their composition and thickness. However, the resistance is typically lower than other alternatives like thermal paste. The goal is to strike a balance between adequate heat transfer and maintaining a proper mechanical interface.
Insulation: Thermal pads also act as electrical insulators, preventing electrical conductivity between the two surfaces they are placed between. This insulation helps to protect sensitive electronic components from potential short circuits or electrical interference.
Durability and Reusability: Thermal pads are often reusable and can withstand multiple installations and removals. Their soft and compliant nature allows them to retain their shape and properties even after being compressed and released several times. This makes them convenient for situations where components might be frequently replaced or upgraded.
Overall, thermal pads offer a reliable and convenient solution for thermal management by providing a conformable, thermally conductive interface between heat-generating components and cooling solutions like heat sinks or heat spreaders.