Copper Heat Sinks? Aluminum Heat Sinks? Does it matter what you make a heat sink from?

True or False?  Heat sink materials make a difference in how efficient a heat sink will be?

Well, like a lot of things in thermal management, it depends on the constraints of your application. Neither copper heat sinks nor aluminum heat sinks are always the default choice.

108K different push pin heat sink assembly configurations featuring 3 different pitch heat sink types, 3 different fin geometries, brass and plastic push pins

 

Recently, ATS performed a study to provide some clarity to users on how different “standard” materials act as heat sinks. Our study included copper heat sinks, aluminum heat sinks and graphite foam heat sinks. We published our article in ECN under the title, “Comparing the Impact of Different Heat Sink Materials on Cooling Performance“.

The results of our study were quite interesting.  As you can see from the following graph, graphite was a good material but not the best. Copper and Aluminum performed better and similarly.

Comparison of copper, aluminum and graphite foam heat sinks

Our conclusions were:

  • Copper and Aluminum are very close in thermal performance. If weight is an issue or cost, then Aluminum is the way to go. The size of your heat sink or the thermal interface material can often make the difference too.
  • Pure copper has about 2x the conductivity of aluminum but that inherent advantage is only helpful when
  1. Air Flow speeds are 800LFM
  2. The hot spot on the CPU or other semiconductor is small in comparison to the size of the chip itself.
  • When air flow is 400LFM or lower or the hot spot on the CPU or semiconductor is spread throughout the chip, then Aluminum is a better choice.
  • The cost of a copper heatsink is often up to 3x the equivalent sized aluminum heatsink
  • Graphite foam-derived heat sinks show promise in specific applications, but exhibit several drawbacks in mainstream electronics cooling.

You can read the full study at ECN by clicking to “Comparing the Impact of Different Heat Sink Materials on Cooling Performance“. You can also check out our earlier conversations on this topic by clicking to our posts, “Is CPU Cooling best done with a Copper Heatsink or Aluminum Heatsink?” and “Intel’s nano-technology breakthrough for heat sinks has R&D promise but real-world applications are in the future; An ATS thermal management technology analysis

Also, if you are a member of Linked-In, there is a Thermal Management group that is worth joining, plus, there is a sub-group off of that focusing on next generation materials for heat sinks. Well worth joining!

One response to “Copper Heat Sinks? Aluminum Heat Sinks? Does it matter what you make a heat sink from?

  1. Loving the information on this site, you have done great job on the content.

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