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dxiw

Disabled
Joined
Feb 7, 2002
I was just wondering for all you true DIY ppl out there try making a waterblock out of graphite heres why.

here is chart of all the thermal conductivities:
http://hypertextbook.com/physics/thermal/conduction/index.shtml

aluminum is 237
copper is 401 (hence better cooler)
silver is 429
diamond is 895!
but whats insanely awesome is
graphite (parallel) at 1950..the only problem is its a non-metal....
it is hard though...

I think it would make an awesome awesome water block if the water cool cool that graphite fast enough...it would never work in a ir cause no fan coud cool a heatsink thats pulls away heat so fast....
what do you guys think about this though?
 
Yeah, but isn't parallel graphite non-waterproof?, almost a felt like material? Adding the binding resin will kill the conductivity numbers.

One more problem, alot of heat conductivity tests were based on electrical conductivity...I doubt most charts I come across since the CuSil debacle.

There is poco foam, a graphite foam with killer surface area. Alas, it too isn't waterproof.

If you find out more about this stuff, pass it on!
 
dxiw said:
but whats insanely awesome is
graphite (parallel) at 1950..the only problem is its a non-metal....
it is hard though...

However:

graphite (perpendicular) 5.7

I suspect it is not easy to find a large chunk of graphite with the crystalline structure oriented in the same direction throughout the chunk. I don't think it all that hard either. Pencil leads are made of graphite combined with clay to make them harder. I'd guess your waterblock might get eroded away by water flowing through it. And they say higher flow is always better:D

Me personally, I'd settle for a diamond big enough to build a waterblock out of.
 
Graphite is an anisotropic form of copper, meaning its properties vary directionally. Note that in the parallel direction graphite is a great thermal conductor, and in the perp. direction it is basically an insulator. The same is true for hardness, in one direction it can withstand high stress but in the other very little shear force.
I am not sure, but I think the strength and conductivity directions are different (check me someone). In other words, if that is true, the direction of high stress strength is a thermal insulator.

Diamond is the isotropic form of carbon (same properties in all directions) which is why it is both hard and thermally conductive regardless of orientation.
 
i dont understand why we dont see nickel plated stuff

nickel is one awsome heat releacer and or absorber

should be sinks of copper coated with nickel


think what a SK800 would do if it was nickel plated
 
i got a better idea guys, someone just build one out of a huge diamond. :) or how about helium 2? ~100,000 it says on teh site lol.
 
AZZKICKER said:
i dont understand why we dont see nickel plated stuff

nickel is one awsome heat releacer and or absorber

should be sinks of copper coated with nickel


think what a SK800 would do if it was nickel plated

er...

we do, i cant think of any examles here (i think there ware some ram sinks) but it works on the same idea as silver or tin plating - it is mearly to fill in the gaps on the base then help thermal conductivity.
 
didn't some heatsink manufacturer have a early tech. sample of graphite hs sometime during last spring.. i remember seeing some stuff of it. too busy to search the archives..
 
it woudl be sweet to jsut have a diamon in side your wb that onyl thouches the core adn then goes in the the water compartment, but i dont think that the water coudl get ath much from it...:D :eh?: :D
 
AZZKICKER said:
i dont understand why we dont see nickel plated stuff

nickel is one awsome heat releacer and or absorber

should be sinks of copper coated with nickel


think what a SK800 would do if it was nickel plated

I think you got confused, Nickel and Tin are terrible thermal conduits. Besides plating is useless, even if its Silver plated. For heatsinks that have poorly soldered fins to the base, Silver plating can help a great deal as it makes a better bonding to the fins and the base.



Thermal Properties of Materials
Thermal Conductivity, W/cm-K
Metals
Aluminum 2.165
Beryllium 1.772
Beryllium-copper 1.063
Brass 70% copper, 30% zinc 1.220
Copper 3.937
Gold 2.913
Iron .669
Lead .343
Magnesium 1.575
Molybdenum 1.299
Monel .197
Nickel .906
Platinum .734
Silver 4.173
Stainless Steel-321 .146
Stainless Steel-410 .240
Steel, low carbon .669
Tin .630
Titanium .157
Tungsten 1.969
Zinc 1.024
 
6502kid said:
Does anybody make a solid silver HS ?

I have seen a solid silver waterclock, was a sprial block....
but its not worth the money for the little gain over copper, and a big hole in your pocket book.
 
6502kid said:
Does anybody make a solid silver HS ?

Back in the day I got a NoiseControl Silverado afer Tom declared it the king of HSF's in 3 straight shootouts (I think it was 3) ... this was when I had a P3/866 which at the time was among the better chips you could buy.

Anyway the thing's base had a chunk of solid silver that weighed... I want to say 500g, don't hold me to that, but it was massive.

It was a great HSF then but I doubt it could do much for today's AMD chips.
 
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