The main property of the thermal pad

There are numerous thermally conductive products on the market, such as thermal pad, thermally conductive silicone sheets, thermal pad, etc., and their manufacturing materials are different, their thermal conductivity is also different, and heat transfer methods are also different. 

There are three main types of heat transfer: convection, radiation, and conduction. Conduction is the way in which heat is transferred as a solid, so it is the way into the heat sink. Conduction occurs when two objects with different temperatures come into contact with each other. Where two objects meet, fast-moving molecules of the hotter object collide with slower-moving molecules of the colder object. When this happens, fast-moving molecules from warmer objects will give energy to slower-moving molecules, which in turn heats colder objects. This process is called heat transfer, and this is how the heat sink removes heat from the computer's processor.

The heat sink is usually made of metal and is used as a thermal conductor to remove heat away from the CPU. However, there are advantages and disadvantages to using various types of metals. First, each metal has a different thermal conductivity level. The higher the thermal conductivity of the metal, the higher the heat transfer efficiency.

One of the most common metals used in heat sinks is aluminum. Aluminum has a thermal conductivity of 235 Watts per Kelvin per meter (W / mK). (In this case, a thermal conductivity of 235 refers to the ability of a metal to conduct heat. In short, the higher the thermal conductivity of a metal, the more heat it can conduct.) The production cost of aluminum is also low, and Lightweight. When the heat sink is installed, its weight will cause a certain degree of pressure on the motherboard to which the motherboard design is adapted. However, lightweight aluminum is beneficial because it adds weight and pressure to the motherboard.

One of the best and most common materials used to make heat sinks is copper. Copper has a very high thermal conductivity of 400 W / mK. However, it is heavier and more expensive than aluminum. But for operating systems that require a lot of heat, copper is often used.

So once the heat is dissipated from the processor through the heat sink, where will the heat be transferred? A fan inside the computer moves air through the heat sink and out of the computer. Most computers also have an additional fan installed directly above the heat sink to help properly cool the processor. Heat sinks with these additional fans are called active heat sinks, while heat sinks with a single fan are called passive heat sinks. The most common fan is a chassis fan, which draws cold air from the outside of the computer and blows it through the computer to expel hot air out of the back.