🚀 go-pugleaf

kludge@grissom.larc.nasa.gov ( Scott Dorsey) writes:

>In article <7926@dirac.physics.purdue.edu> parks@gibbs.physics.purdue.edu (Chris Parks) writes:
>>
>>What is a good material (good=price + availability) which is
>>an electrical insulator and a good conductor of heat?
>>
>>It will be used at temperatures as low as 4.2 Kelvin and it needs
>>to hold up to about 200 volts / mm, heat conductivity needs to
>>be comparable to copper.  Does it exist?

>If it weren't for the low temperature requirement, I would recommend some
>of the silicone compounds, which are very good heat conductors.  Mica is
>right out.  Are there any silicones that are useful at temperatures that
>low?
>--scott
 You don't specify how big, but diamond might be a candidate if the insulator 
is only a millimetre or so across and less than that thick. For instance,
from the Chemical Rubber Company Handbook:

		Material                   K (W/cm.k) - at 273 K

		  Cu			      4.03

		Type IIa diamond	      26.2

	  	Type IIb diamond	      15.2

		Type I   diamond	      9.94

I have in the past seen adverts for diamond heat sinks at remarkably low 
prices (tens of dollars if I remember correctly), so they might not be right
out for your application.
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