Anyone know the exact percentages of CuSil?

[Szech]

I agreed to do some research for this metal lab, and I was thinking about making some. That thermal conductivity is sure mouth watering =P.

Thanks!

 

[It_The_Cow]

The site is down but it's located on the topics section under peltiers and copper cold plate comparison in the front page

 

[BboySkid]

i suspect you are talking about CuSi

that "L" just bugged me, sorry for being so picky hehe

 

[William]

BboySkid (May 29, 2001 07:41 p.m.):
i suspect you are talking about CuSi

that "L" just bugged me, sorry for being so picky hehe

no, that would be copper silicide which doesn't even remotely exist. The Cusil is a mixture of copper and silver to provide the best thermal conductince. Why you would want to dope down copper is beyond me.

 

[CreePinG_DeatH_reverted]

I don't remember the exact percentages for CuSil, but I will NEVER forget the price. For a 40mm by 40mm by 5mm shim cost around $1,500.00 U.S. That was the quote from the metal company in the Heat Conductivity article.

 

[Szech]

Wow that's expensive. Anyway, I don't plan on buying it, I plan on making it. Ha! It was funny when he was showing me around the lab today, because he showed me the room where they melt metals, and the first thing I thought about was making some CuSil. I asked how high temperatures the machine could get, and if it would mix the metals, and if it would make alloys, and how solid the alloys were. He told me that whatever you throw in the top part can be mixed into an alloy, and that if you let it cool slowly, the metal grains would line up better than the metal you start with. I can understand why a company would charge so much for it. It is a 8!+C# to set up the machine. But you know what? I'll bet that it's not much more for another 5 pounds. Once it's set up, it's easy to churn out a lot.

 

[GOD]

28%Cu,72%silver.
got a cold plate made with the stuff.
wanted to get a water block made but was so expensive.

GOD...

 

[Ridenow]

dunno260 (May 29, 2001 08:35 p.m.):

BboySkid (May 29, 2001 07:41 p.m.):
i suspect you are talking about CuSi

that "L" just bugged me, sorry for being so picky hehe

no, that would be copper silicide which doesn't even remotely exist. The Cusil is a mixture of copper and silver to provide the best thermal conductince. Why you would want to dope down copper is beyond me.

Silver is Ag so we should call is Cuag, but that sounds funny. Silver is the one with the better conductivity, so it is acually the cheaper copper "doping down" the silver.

 

[Szech]

Ooh, thanks

Oh, uh, one more question. 72% Silver 28% copper... does that mean I need to melt say, 72 grams of silver, and 28 grams of copper? Or do I have to divide 72 by the atomic weight of Silver, and divide 28 by the atomic weight of copper to get the proportions?

 

[Ridenow]

Wow, this is the first time I double posted. All because I could not spell chemestry the first time.

 

[Ridenow]

It does not matter if you did it using grams or went though the trouble of atomic mass. You would get the same percentage. Think about it, mass is mass, it does not care if you measure it in grams, pounds, atomic units or elephants.

Shame on you for making me remember chemistry class.

 

[Szech]

Don't mean to bring back any bad memories, I didn't like chemistry much either

What I mean is: Does the percentage indicate the ratio of the mass of copper to silver? Or is the percentage the ratio of copper atoms to silver atoms? If it's the former, then it's just a matter of weighing out a ratio of 72 grams of silver to 28 grams of copper. If it's the latter, then I'd have to weigh out 72 / 107 (107 is the atomic weight of silver) grams of silver to 28 / 63 (63 is the atomic weight of copper) grams of copper. In which case, I would have to mix 60 grams of silver to 40 grams of copper.

 

[William]

Ridenow (May 30, 2001 04:37 p.m.):
It does not matter if you did it using grams or went though the trouble of atomic mass. You would get the same percentage. Think about it, mass is mass, it does not care if you measure it in grams, pounds, atomic units or elephants.

Shame on you for making me remember chemistry class.

but what if it isn't by weight, but by moles? That would make a huge difference. You are right though, as long as you use the same weighing system it doesn't matter. I would suspect they are talking about weight, but make sure it isn't moles, if it is, you have totally different weights to put in. That is what Szech is trying to get at, and it is very very good point. Anybody know? I woudl suspect weight, but you never know.

 

[CreePinG_DeatH_reverted]

I doubt it's by weight. If it was by weight you have to find out the actual weight of each atom and such. It might be easier to use parts, since it's by mass. So get together all the pure substances that you need, choose a standard, i.e. grams, lbs, tons, and divide them equally... 78 parts of silver and 22 of copper. Hey if I send you money can you make me a big thick ole block? You won't have to cut it out or anything. I can get someone else to do that. thick block is like 4 inch cube.

 

[GOD]

it is pecentage of volume.
not mass sorry....
hope this answer your question.

GOD....

 

[William]

CreePinG_DeatH (May 30, 2001 07:22 p.m.):
I doubt it's by weight. If it was by weight you have to find out the actual weight of each atom and such. It might be easier to use parts, since it's by mass. So get together all the pure substances that you need, choose a standard, i.e. grams, lbs, tons, and divide them equally... 78 parts of silver and 22 of copper. Hey if I send you money can you make me a big thick ole block? You won't have to cut it out or anything. I can get someone else to do that. thick block is like 4 inch cube.

on the earth, weight and mass are the same things.