• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Tell me what you think about SILVER in my heat sink ?

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

goman

Registered
Joined
Feb 8, 2001
Location
Ohio
I have a question about heat sinks. This is what I want to do. I have a few 1oz. blocks of silver ( just laying around ) and I was thinking that silver is a much better conductor than Aluminum (or copper ) and it should make for better heat transfer, now I don't have enough Silver to build an entire heatsink out of, and I don't have a means of making a shim out of Silver.
What I think I can do is mill the center out of my aluminum HS a little larger than the core of my T- Bird about a quarter inch deep the mill several runners out from that then pour the Silver in to the Aluminum. This would serve to increase the serface area of the core with an excellent heat transfer to the aluminum and increase cooling.
Tell me what you think?? By the way PAT.PEND.!!
 

DamnFast

Member
Joined
Feb 1, 2001
I really don't know how it will perform but...well it might work.
In my opinion though, try to make a thin layer of silver and attatch it to the bottom of the aluminium heat sink. Have you seen those copper sheet at the bottom of Alpha PEP66? That's the idea. Instead of copper, just use the silver. I don't know how much more cooling it will provide but it should if everything goes right. Bare in mind that metal-to-metal bonding is not an easy job.
Good luck.
 
OP
G

goman

Registered
Joined
Feb 8, 2001
Location
Ohio
Thanks for the input and by the way the PAT PEND. thing was a joke.
 

markedmundb

Senior Member
Joined
Dec 18, 2000
Location
Kent, UK
I don't remenber what hardware site it was... or when it was up... but someone placed (stuck?) a lapped "real silver" (as opposed to the nickel-based alloy of ordinary 'silver-coloured' coins) coin on the bottom of the sink.

I can't remember when or where or what the results were, but it's bound to be out there.

Who knows, folk have posted links for stuff I brought up before, they might do it again... :¬)}
 

AKDUDE

Senior Member
Joined
Feb 13, 2001
I always thought that since copper and silver were so close, it would not make that much of a difference.. I guess I could be wrong though.

The 19.99 poly/copper blocks that guy has are a great idea! Looks pretty neat too
AKDUDE
 

LimeyGreg

Senior Member
Joined
Dec 20, 2000
Location
Los Angeles
When you pour the liquid silver into the milled block have you considered the coefficient of expansion?. As it cools will the silver shrink more than the aluminum? If so, you will get separation of the silver from the aluminum - I don't think the resulting airgap will help with the thermal conductivity characteristics too much. Secondly, you are introducing another thermal interface which may negate any gains you get from using silver.

Incidentally, there is also an alloy called CuSil that has better thermal conduction than silver, maybe you could smelt copper and silver together and then cast a heatsink.
 
OP
G

goman

Registered
Joined
Feb 8, 2001
Location
Ohio
Well thanks for all the input !! I didn't really expect to get this much.
There were many good points and suggestions. I will take all of them into consideration when I finally decide to try and build my own HS.
To ALL that have helped I will surely share my riches. Thanks to all.
 

klosters64a

Senior Member
Joined
Dec 17, 2000
Location
Seattle, Wa
I'm sure not a metallurgist, OK? I also don't know how how Alpha bonds the thin copper to the bottom of their aluminum HS's. It can be difficult to weld dissimilar metals together. It's possible that molten silver won't adhere to aluminum. I dunno, unfortunately.

It's a good idea! Please keep us informed!
 

Peekaboo

New Member
Joined
Feb 3, 2001
The thermal conductivity of silver and copper are nearly identical (2x alum) but the heat dissapation of both is about half that of aluminum.
Complicating matters is the fact that heatsinks for GPU's and memory chips are hung upside down so they nearly always cry out for active cooling.
I use a silver solder shim .005 thick between my GPU and Blorb. I feel it "spreads" the heat outward to the most active area for the fan.
 

Hoot

Inactive Moderator
Joined
Feb 13, 2001
Location
Twin Cities
If you pour molten silver onto/into an aluminum HSF, it will fall right through, barely slowing down, because of
the difference in melting points between the two. I do copper to copper and copper to steel CADWELDS for grounding radio towers and molten copper is very hot. I'm sure molten silver is around the same temp.

Hoot
 

Ammethyl

Registered
Joined
Feb 27, 2001
CuSil

LimeyGreg (Feb 20, 2001 11:29 p.m.):
When you pour the liquid silver into the milled block have you considered the coefficient of expansion?. As it cools will the silver shrink more than the aluminum? If so, you will get separation of the silver from the aluminum - I don't think the resulting airgap will help with the thermal conductivity characteristics too much. Secondly, you are introducing another thermal interface which may negate any gains you get from using silver..
Good point here.

Incidentally, there is also an alloy called CuSil that has better thermal conduction than silver, maybe you could smelt copper and silver together and then cast a heatsink.
I'm no metallurgist, by I think the extreme price of CuSil comes from the difficulty of "mixing" both metal. I think it doesn't suffice to simply molten both, mix 'em and let it cool. It wouldn't "disolve" Would be a waste of this preciuos silver (since it may still be unrecuperable)