Lämpösiirtopasta

Lämpösiirtopasta, known in English as thermal paste or thermal compound, is a thermally conductive material applied as a layer between a heat-generating component and a heat sink. Its primary purpose is to fill microscopic air gaps between the two surfaces, which are inevitable even with highly polished components. Air is a poor conductor of heat, so by displacing it, the thermal paste significantly improves the efficiency of heat transfer from the component to the heat sink.

The composition of thermal paste varies, but it typically consists of a base fluid and conductive fillers. Common fillers include metal oxides like aluminum oxide or zinc oxide, as well as metallic particles such as silver or aluminum. Some high-performance pastes may also incorporate ceramic or even diamond particles for enhanced thermal conductivity. The base fluid acts as a carrier for these particles and can be silicone-based, ceramic-based, or hydrocarbon-based.

Thermal paste is essential in many electronic devices where components generate significant heat. This includes CPUs and GPUs in computers, power transistors in amplifiers, and LED lighting systems. Without adequate thermal paste, heat would build up in the component, leading to performance throttling, reduced lifespan, or even permanent damage. Application is typically a small dot or line of paste on the component's surface before the heat sink is mounted, allowing pressure to spread it evenly. The paste should be reapplied periodically as it can dry out or degrade over time.