Pyrolytic carbon - Overclock.net

Uberleet Superninja · 04-23-09

Has anyone tried using Pyrolytic Carbon instead of copper for the heat transfer properties? I'm considering purchasing a chunk and sanding it down to use as a cold plate for my pelt setup.

MiNTEQ seems to market the material for chip cooling actually:

PYROID® HT matches the thermal performance of CVD diamond at 1700 W/mK and substantially better economics. Available in sheet form up to 30 cm2 and any thickness ranging from 0.25 mm to 1.3 mm, this material is ideal for high-volume production and provides economic value at the device assembly level.

Thermal Conduction Comparison

GREATER THAN 4 X COPPER AND NATURAL GRAPHITE

GREATER THAN 5 X AIN AND BeO SPEADER MATERIAL

This exciting new material offers high tensile strength and a significant increase (90 times) the flexural modulus of existing natural graphite spreader materials.

And we can engineer the Coefficient of Thermal Expansion (CTE) planes to carefully match the substrate and solder conditions to maintain the joint integrity.

http://www.minteq.com/our-products/m...ytic-graphite/

Hueristic · 04-23-09

What's the cost? Standard solder?

Uberleet Superninja · 09-18-09

Hueristic: Not sure about the solder, been too busy with a million other projects to look into this further.

However, I did come across a few links from ORNL that could be of interest:
http://www.ms.ornl.gov/researchgroup...atsci-2003.pdf
http://www.ms.ornl.gov/researchgroup...lectronics.pdf

The cost looks to be about $50 for a 3x3" slab of pyrolytic carbon and $75 for a chunk of graphite foam, there's actually a manufacturer that makes the exact materials provided in the links above AND sells them to the general public without requiring bulk orders, I will post the link as soon as I find it.

A water block with graphite foam bonded to pyrolytic carbon seems like it would be fairly insane...

Sorry for not updating this thread, I just wanted to get the idea out there but didn't have the time to follow up. Considering the density and thermal output of electronics is quickly increasing it seems like we'll hit a point sooner or later where copper and aluminum will no longer be sufficient.

Uberleet Superninja · 09-18-09

Poco Graphite:
http://www.pocographiteonline.com/servlet/StoreFront

DuckieHo · 09-18-09

Quote:

Originally Posted by Uberleet Superninja

Hueristic: Not sure about the solder, been too busy with a million other projects to look into this further.

However, I did come across a few links from ORNL that could be of interest:
http://www.ms.ornl.gov/researchgroup...atsci-2003.pdf
http://www.ms.ornl.gov/researchgroup...lectronics.pdf

The cost looks to be about $50 for a 3x3" slab of pyrolytic carbon and $75 for a chunk of graphite foam, there's actually a manufacturer that makes the exact materials provided in the links above AND sells them to the general public without requiring bulk orders, I will post the link as soon as I find it.

A water block with graphite foam bonded to pyrolytic carbon seems like it would be fairly insane...

Sorry for not updating this thread, I just wanted to get the idea out there but didn't have the time to follow up. Considering the density and thermal output of electronics is quickly increasing it seems like we'll hit a point sooner or later where copper and aluminum will no longer be sufficient.

How do you plan on bonding graphite and pyrolytic carbon? Are they strong enough to be machined?

Hueristic · 09-18-09

W0W I completely forgot this thread, you just hurt my brain!

I just checked the links and .25 mil sounds pretty good. Is it soft enough to spread or is it brittle? Sounds like it would e easier to work with than diamond dust and if it's a soft graphite it should give good contact.

Make sure to get some pics.

Looking forward to this.

NidStyles · 09-20-09

Have fun working with it. It's very brittle, and it only conduct's heat along the vertice of the carbon alignment. In other word's, it only work's in one way. No matter how you try to cool it, the vast majority of the heat will be along the edge of it. Thusly will work to remove the heat from the CPU just fine, but have fun trying to cool the graphite, which is in effect a ceramic element.

The only way I it work's better than copper is to use extremely thin sheet's of it lined up and water flowing along the alignment at the edge of the sheet's. Then there's numerous difficulties to get around. I'll be nice and list them clearly, just in case you do decide to try this.

* Aligning the layer's for maximum heat transfer.

* Handling thin enough sheet's in a manner that will not break them.

* Adhering the sheet's with a material, bubble free without cracking, or breaking the sheet's.

* Preventing erosion on the end's of the sheets without reducing thermal transfer.

* Mounting the sheet's with sufficient pressure to allow heat transfer without cracking, or shattering them.

Don't get me wrong, it's actively used in military, and space program's for the exact use you wish to use it for, but there's difficulties in manufacturing that are not really cost effect for the consumer market. this is why we haven't really seen these on the open market as of yet.

Hueristic · 09-20-09

Quote:

Originally Posted by NidStyles

Have fun working with it. It's very brittle, and it only conduct's heat along the vertice of the carbon alignment. In other word's, it only work's in one way. No matter how you try to cool it, the vast majority of the heat will be along the edge of it. Thusly will work to remove the heat from the CPU just fine, but have fun trying to cool the graphite, which is in effect a ceramic element.

The only way I it work's better than copper is to use extremely thin sheet's of it lined up and water flowing along the alignment at the edge of the sheet's. Then there's numerous difficulties to get around. I'll be nice and list them clearly, just in case you do decide to try this.

* Aligning the layer's for maximum heat transfer.

* Handling thin enough sheet's in a manner that will not break them.

* Adhering the sheet's with a material, bubble free without cracking, or breaking the sheet's.

* Preventing erosion on the end's of the sheets without reducing thermal transfer.

* Mounting the sheet's with sufficient pressure to allow heat transfer without cracking, or shattering them.

Don't get me wrong, it's actively used in military, and space program's for the exact use you wish to use it for, but there's difficulties in manufacturing that are not really cost effect for the consumer market. this is why we haven't really seen these on the open market as of yet.

Good info, thx.

reedo · 09-20-09

moar plz this sounds like an amazing use for the collective brainpower of ocn(at least those of you who are smarter than me)

Blameless · 09-20-09

Quote:

Originally Posted by NidStyles

it only conduct's heat along the vertice of the carbon alignment. In other word's, it only work's in one way. No matter how you try to cool it, the vast majority of the heat will be along the edge of it. Thusly will work to remove the heat from the CPU just fine, but have fun trying to cool the graphite, which is in effect a ceramic element.

This is what the manufactuer says about it:

Quote:

PG has excellent thermal conductivity, approaching copper in the a-b direction, whereas it acts almost as a ceramic on the 'c' direction. In an annealed PYROID® HT state, the thermal conduction properties increase up to four to eight times that of copper and aluminum, respectively (thermal conductivity as high as 1700 W/m°K). We are able to selectively bond the planes through special fixturing to take maximum advantage of its directional conductivity. In this regard it is an excellent material in special thermal management applications, including lids and heat sinks.

So, it's the edges that act as a ceramic, not the large area faces.

04-23-09	#2 (permalink)
Hueristic Need a New Protocol Join Date: Jul 2008 Location: Bottom_Of_A_Bottle Posts: 7,758 Rep: 317 Unique Rep: 214 Folding Team Rank: 65 Trader Rating: 2	What's the cost? Standard solder? __________________ I seldom argue my advice, It's free take it or leave it. READ this thread before starting your first build!!! ALWAYS power up a Mobo Before installing it! Consider Less than helpful posts as Free Bumps. ¡¡¡ʍʇɟ qn1ɔ uoıʇɐıɔǝɹddɐ 939 ʇǝʞɔos ǝɥʇ: [Official]November Foldathon Retro Rulez *This goes without saying but* 1. If you can't afford to lose it don't mod or OC it. 2. At least read the OP before commenting. Semper Fi

09-18-09	#6 (permalink)
Hueristic Need a New Protocol Join Date: Jul 2008 Location: Bottom_Of_A_Bottle Posts: 7,758 Rep: 317 Unique Rep: 214 Folding Team Rank: 65 Trader Rating: 2	W0W I completely forgot this thread, you just hurt my brain! I just checked the links and .25 mil sounds pretty good. Is it soft enough to spread or is it brittle? Sounds like it would e easier to work with than diamond dust and if it's a soft graphite it should give good contact. Make sure to get some pics. Looking forward to this. __________________ I seldom argue my advice, It's free take it or leave it. READ this thread before starting your first build!!! ALWAYS power up a Mobo Before installing it! Consider Less than helpful posts as Free Bumps. ¡¡¡ʍʇɟ qn1ɔ uoıʇɐıɔǝɹddɐ 939 ʇǝʞɔos ǝɥʇ: [Official]November Foldathon Retro Rulez *This goes without saying but* 1. If you can't afford to lose it don't mod or OC it. 2. At least read the OP before commenting. Semper Fi

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Pyrolytic carbon

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