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Electrically isolating, thermally conductive coating for SST

I am looking to coat stainless steel with an electrically isolating, but thermally conductive coating. It has to stand up to about 500C operating temp & be somewhat "tough". Any suggestions?

Steve Ayres
product designer - Northville, Michigan
January 31, 2008

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First of two simultaneous responses -- February 2, 2008

Hello Steve,
Although it seems to be joking the best heat conductor among electric isolators (dielectrics) is diamond. Really. But seriously, PTFE is quite good heat conductor, but very good eletric isolator.

Best regards

Janusz LABEDZ
Aurotech - Warsaw, Poland

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Second of two simultaneous responses --

Its just a matter of how thermally conductive and how electrically insulating you want it to be. If I remember well based on physics, most anything that is a good thermal conductor is also a good electrical conductor. All plastics are out, obviously. Ceramics are also out. Maybe only some intermetallic compounds but they will be very thin, like Titanium nitride or similar.

Guillermo Marrufo
Monterrey, NL, Mexico
February 2, 2008

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It should be coating of less or equal to 2-5 micron thickness made from dialectic such as Al2O3, MgO, CaO or similar. The specific conductivity is very low, and thermo conductivity will good enough for such thin layers.

Anna Berkovich
Russamer Lab

Pittsburgh, Pennsylvania

February 7, 2008

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February 21, 2008

Depending on financial aspects diamond is really an alternativ to think about! It can be plated as DLC (diamond like carbon) via PVD.

Greets from Munich
Franz

Franz Gassner, chemist
Automobile production - Munich, Bavaria, Germany