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Hard Anodize -Thermal/Dielectric Properties

 

I'm planning on using a hard anodize on an aluminum part used as a heatsink, but also require it to be an isolator (dielectric). Does hard anodize meet this requirement and does it affect the thermal conductivity of the aluminum at all?

Thanks,

Fidel Aragon
- Santa Clara, California

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Hello Fidel,

Hard Anodize (type III) is used often for this application, offering extremely good dielectric properties. Type II anodize also offers good insulation At a lower expense. Have some samples produced by your local anodizer and compare.

Bill Grayson
- Santa Cruz, California, USA
 

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An anodized finish is definitely a good electrical insulator and heatsinks are often anodized. I wasn't able to conveniently find the thermal conductivity of the coating, but some of the best frying pans are hard anodized aluminum, so it's not bad.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
 

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January 4, 2010

A GREEN technology alternative is to make use of a thermally conductive dielectric ink to coat the aluminum.

Simply print about .001" and thermally cure the ink.

The technology is new but is proving to be very exiting!

mike dubois
- mississauga, Ontario, Canada

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January 4, 2010

Hi, Mike. Thanks for advising us of this alternative. But what do you see as un-green about anodized aluminum? Laptop computer manufacturers are switching to anodized aluminum cases as a green technology so they can stop using organic compounds like plastic.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey