Thermal conductivity (ceramics)

[George Herold]

Sure... but it beats the snot outta 1 mil of Kapton.

George H.

 

[Jon Kirwan]

Amorphous diamond is coal. ;-)

Hehe.

I'm thinking of vapor deposited kind. But... yes, that too.

Jon

 

[Jon Kirwan]

<snip>
I was thinking that Beryllium oxide might be the penultimate.
(non-electrical conductor ).

Looks darned good. I just hope they make the stuff safely.
Machining beryllium metal is dangerous (but it has useful
thermal expansion and heat dissipation characteristics.) I've
used it before in places where the expansion needed to be
very low. But hiring machinists for that is a different
story.

Jon

 

[Spehro Pefhany]

A thread that ends happily?

 

[George Herold]

Looks darned good. I just hope they make the stuff safely.
Machining beryllium metal is dangerous (but it has useful
thermal expansion and heat dissipation characteristics.) I've
used it before in places where the expansion needed to be
very low. But hiring machinists for that is a different
story.

Jon

My only contact with Beryllium was ordering a 6 inch diameter dome
from Brush-Wellman. It was the end of the vacuum chamber for an
electron beam... right above the beam dump. Only 5mil thick at the
center.

George H.

 

[George Herold]

I still can't see how thin sheets of this stuff are useful. It has
good thermal conductivity in the X and Y axis, in the plane, but it's
rotten in Z.

OK the floating above a magnet thing is cute.

I think the two dimensional nature of the flow gives it the rather
long/large thermal diffusivity. It's somehow a measure of the length
where heat flow changes from linear to diffusive. (Thermal
'resistance' becomes more than linear in length.)

So if you're moving heat around, this may take it a bit further..(?)
(Be fun to have some, next digikey order maybe.)
Mind you I don't really know much about it. I still have to measure
diffusivity in something simple like copper.

George H.

 

[George Herold]

We had a generator from HP that advertised the Be substrate on the
output diver with a warning inside the case.  Our industrial safety
people just about had a cow.  They generators were all pulled until
they got a statement from HP that they were safe to use.  No one said
they were bright

(the security people there would only put a lock on

one door to the lab because two would only be half as secure).- Hide quoted text -

Hmm, if we could just brick you into the lab with no door it'd be
totally secure.

Of course anything nuclear is very scary. We shipped our proton NMR
spectrometer over to Canada for a trade show. Someone spelled out
nuclear magnetic resonance and we had all sorts of problems.

George H.

 

[tm]

I carry around a NUCLEAR POWERED LIGHT SOURCE on my key ring.

Watch you don't get on some libtards' EPA list.

George, that's why they call it MRI instead of NMRI. The world has been
dumbed down in science.

 

[George Herold]

I carry around a NUCLEAR POWERED LIGHT SOURCE on my key ring.

--

John Larkin         Highland Technology, Inc

jlarkin at highlandtechnology dot comhttp://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro   acquisition and simulation- Hide quoted text -

- Show quoted text -

Grin, of course unless it's on a gun site it's illegal in the US.

George H.

 

[Tim Williams]

I still can't see how thin sheets of this stuff are useful. It has
good thermal conductivity in the X and Y axis, in the plane, but it's
rotten in Z.

If you run the numbers, it's something like 4x better than copper in
lateral spreading, but more than 4x more expensive by volume, so you save
absolutely no cost in using it. Plus the copper is solderable. It is
thinner, but any application where you don't have 0.3 mm to spare needs a
serious thermal redesign, regardless.

Tim

 

[[email protected]]

(the security people there would only put a lock on

Hmm, if we could just brick you into the lab with no door it'd be
totally secure.

That was suggested.

Of course anything nuclear is very scary. We shipped our proton NMR
spectrometer over to Canada for a trade show. Someone spelled out
nuclear magnetic resonance and we had all sorts of problems.

Nuclear. This was IBM in the '70s. The most dangerous things we had
behind the door were a few wire wrap guns.

 

[[email protected]]

Grin, of course unless it's on a gun site it's illegal in the US.

Oh, NO! WMDs are legal! We'll have to get Larkin's Senator on that,
right away!

 

[josephkk]

I was thinking that Beryllium oxide might be the penultimate.
(non-electrical conductor ).

George H.

I think that there are forms of boron nitride that beat it.

?-)

 

[[email protected]]

I hope those weren't fully automatic.

Nope, not even stripper clips. The were even muzzle loaders.