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When attaching the heat-sink-and-cooling-fan to a modern computer Central Processing Unit (CPU), it is considered Best Practice to employ a substance in-between the two, usually known as Thermal Paste. See, the top of the CPU is not necessarily perfectly smooth, nor is the bottom of the heat sink.
Thermal paste fills all the microscopic crevasses, so that more heat can be transferred from the CPU to the heat sink.
One of the components of better-quality thermal pastes is particles of metallic silver, since silver is the best metallic heat conductor. However, silver is NOT the best SOLID heat conductor. That honor goes to diamond. (Diamond is so hard that thermal vibrations are handled just like sound-wave vibrations, and so heat gets transmitted through diamond at a rate of thousands of meters per second.)
Well, it happens that recent years have seen the development of easy ways to make large quantities of microscopic diamonds (via "vapor deposition" in a vacuum). That means it should be easy enough -- and cheap enough! -- to mix them into a superior thermal paste.
At least halfbaked before
"It was also superior to diamond and carbon nanotube based pastes currently undergoing development." [Worldgineer, Nov 04 2004]
Carbon black paste, put to the test
NOT as good as "Arctic Silver" [Vernon, Nov 05 2004]
(?) Various thermal pastes under pressure
The third of a three-page article, with a little more detail than [Worldgineer]'s link. 0.46MPa is 460,000Pascals (M=Mega). [Vernon, Nov 05 2004]
Somebody has actually now gone and done it. [Vernon, Aug 05 2009]
For a more thorough baking...
Appears to be available to whoever wants it. [Vernon, Aug 05 2009]
Cultured diamond factory in Florida [Gamma48, Aug 06 2009]
Struers diamond pastes/polishes
Used in the preparation of metallographic samples. [Gamma48, Aug 06 2009]
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||Sounds plausible to me (but then I know little of the ins and outs of attaching CPUs to heat sinks)
||Thanks, [Worldgineer]; in a week or two I'll probably make myself delete this as not being original enough. Until then, others can read this and know I'm still around, if nothing else. :)
||Great idea either way. (note: I found the original article and updated my link)
||I've also done some looking around, and maybe I won't have to delete this. See, apparently the carbon black paste is only as good as other pastes, until pressure is applied. THEN it goes way up. BUT, most computer chips can't take that kind of pressure, if you want to attach a heat sink to it.
||Meanwhile, the experiments about diamond paste were apparently using diamond dust from, say, the jewelry business. Those particles are TOO BIG! The vapor-deposition diamonds I mentioned should be available in much smaller sizes.
er... you know what I mean.
||[Vernon] standard atmospheric pressure is about 0.1MPa (1bar is roughly atmospheric pressure due to the bar being defined as 0.1MPa)
||+. Seems plausible. What I don't quite
understand is what you've done with
[vernon], imposter! This is impossibly
short for a 'real' [vernon] posting. ;)
||"Scientists have now recorded the highest thermal conductivity ever observed for a solid above liquid nitrogen temperatures, 410 W/cm-K, in 99.9%-pure C-12 at 104 K. The researchers predict that the thermal conductivity for 99.999%- pure C-12 diamonds would exceed 2000 W/cm-K and that integrated circuits mounted on such diamonds (cooled in liquid nitrogen) could operate at 500 times the power density of circuits mounted on copper substrates at room temperature." (Lanhua Wei et al., Physical Review Letters, 14 June 1993.)
||whooooa!!! So the trouble is manufacturing them
||...Would probably make a great grinding paste as well.
||Thermal conductiviy is one reason diamonds are called "ice". They conduct heat from your hands so diamonds feel cold to the touch.
Cultured diamonds are big business (link).
There's quite a market for diamond polishes (i.e. polishes which are made partly from diamonds, natural or synthetic) too.(link)