Aluminum Heat Sinks absorb and dissipate excess heat. Their alloys include 3000 & 6000 series aluminum. Heat Sink aluminum alloys depend on the application and are used in LED designs. They may also consist of one or more flat surfaces to ensure good thermal contact with the components of electronic devices that need to be cooled, and an array of aluminum comb or fin-like protrusions to increase the surface contact with air, and thus the rate of heat dissipation.
Aluminum Heat Sinks can be produced into desired shapes by the following cost-effective processes using progressive stamping or roll-forming for low density thermal requirements. Aluminum and copper are very close in thermal performance, although if weight or cost is an issue than aluminum is the winner and should be the metal of choice. Aluminum Heat Sink Alloys include 1000, 3000, and 6000 series.
References:
Krause, A. "The Heat Sink Design Procedure"
Lee, S. "Optimum Design and Selection of Heat Sinks"