Thermal paste, also known as thermal compound or thermal grease, is a substance used in computer systems to improve the thermal conductivity between a heat-generating component, such as a central processing unit (CPU), and its heat sink. Its primary purpose is to fill in microscopic gaps and imperfections between the mating surfaces of the component and the heat sink, which helps to maximize the transfer of heat from the component to the heat sink.
When a computer component, such as a CPU, operates, it generates heat. To prevent overheating, a heat sink is typically attached to the component. The heat sink absorbs the heat and dissipates it into the surrounding environment. However, the surfaces of the component and the heat sink are not perfectly smooth, and air can become trapped in the gaps and imperfections between them. Air is a poor conductor of heat, so the presence of air pockets can hinder the efficient transfer of heat.
Thermal paste fills in these gaps and improves the contact between the two surfaces, creating a more efficient thermal pathway for heat to flow from the component to the heat sink. It typically consists of a combination of thermally conductive particles suspended in a silicone-based or metal-based compound. The thermally conductive particles, such as metal oxides, enhance the thermal conductivity of the paste.
When applying thermal paste, a small amount is usually spread evenly over the surface of the heat-generating component. The heat sink is then placed on top, allowing the paste to spread and fill any gaps as the two surfaces are pressed together. This helps to eliminate air pockets and improve thermal transfer.
The application of thermal grease offers several benefits in computer systems and other electronic devices:
Improved thermal conductivity: The primary benefit of thermal paste is the enhancement of thermal conductivity between a heat-generating component and a heat sink. By filling in gaps and imperfections, thermal paste creates a more effective transfer of heat from the component to the heat sink.
Reduced temperature: Efficient thermal conductivity leads to lower temperatures for the heat-generating component. When the heat is effectively dissipated through the heat sink, the component can maintain optimal operating temperatures.
Prevention of air pockets: Air pockets or gaps between the component and the heat sink hinder the transfer of heat. Thermal paste eliminates these air pockets by filling in the microscopic imperfections and creating a continuous thermal pathway.
Even distribution of pressure: Thermal paste acts as a cushioning material between the component and the heat sink. It helps to ensure even distribution of pressure across the mating surfaces, avoiding uneven contact and potential damage.
Easy installation and removal: Thermal paste is relatively easy to apply and remove. It usually comes in a syringe or small container, and a thin layer can be evenly spread on the component using a thermal paste applicator or other suitable tools.