Aluminium Extrusion Sections Heat Sink Heat sinks are used with high-power semiconductor devices such as power transistors and optoelectronics such as lasers and light emitting diodes (LEDs), where the heat dissipation ability of the component itself is insufficient to moderate its temperature. ... A heat sink is usually made out of aluminium or copper
Aluminum is lightweight easy to manufacture and cost effective, making it an ideal choice for most heat sinks. Alloys 6061 and 6063 are the most common alloys while 1050 and 1100 is purer with slightly higher conductivity. Its ability to move heat, thermal conductivity, is about half of copper.
Secondly, Aluminium is a lightweight metal, which is also another property that other metals do not possess. Heat sinks are mainly used inside computers to cool down the CPU(Central Processing Unit), they are also used in lighting devices, LEDs, and power transistors.