Heat sink is a kind of heat dissipation device for the electronic components in electrical appliances, mostly made of aluminum alloy, brass or bronze plate, fin, multi-fins and so on. Commonly used heat sink material is copper and aluminum alloy, both have their advantages and disadvantages. Copper conducts heat well, but it is expensive, difficult to process, heavy (many pure copper heat sinks exceed the weight limit of the CPU), small in heat capacity, and easy to oxidize. Pure aluminum is too soft to be used directly. For ordinary users, the use of aluminum heat sink is enough to meet the heat dissipation needs.
Heat sink material
Heat sink material refers to the specific material used by heat sink. As for the heat sink material, the thermal conductivity of each material is different. The thermal conductivity is arranged from high to low, namely silver, copper, aluminum and steel. But silver would be too expensive to use as a heat sink, so copper is the best solution. Although aluminum is much cheaper, it clearly does not conduct heat as well as copper (about 50% as well). At present, the most commonly used heat sink material is mainly copper and aluminum , both have their advantages and disadvantages. Copper has good thermal conductivity, but it is very expensive and difficult to process, too heavy (many full copper heatsink exceed the weight limit of the CPU), small in heat capacity, and easy to oxidize. While pure aluminum is too soft to be used directly, only the aluminum alloy used can provide enough hardness. The advantage of aluminum alloy is low price, light weight, but the thermal conductivity is much worse than copper. Some of the heat sink make good use of each strength, in the aluminum heat sink base embedded a copper plate.
How does heat sink work?
1. Heat absorption -- absorb heat from hot objects with small volume and area, so that the temperature will not rise sharply due to heat accumulation, leading to various undesirable consequences
2. Heat conduction -- transfer the absorbed heat internally to each part of the radiator, making full use of the large heat capacity and surface area
3. Heat dissipation -- heat is lost to the air through various heat exchange channels on the surface (mainly heat convection) (forced convection with fans is possible)