Copper vs. aluminum

[CU later]

Copper will make a better heatsink.
http://www.overclockers.com/articles223/

[Joe]

(edited - I was young and stupid!)
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C-ya
Joe

[CU later]

Hmmmmm.......On your page you say

"Now I am NOT an expert or a person holding a PHD in physics, or thermo dynamics, so I may be a lil off, but the theory should be correct hehehe If you have a PHD or just know yer stuff, and see me screw up some fact, please email me and let me know!

So I shoot you an email because I (and many others) know that your ideas on this subject are clearly wrong.

Even if you don't agree with me you didnt have to post my name email AND address on your site.

NO CLASS.


As far as my education goes......I'm not too concerned.

"Aluminum's Molecules are spread apart more, leaving more space between the molecules. This makes Aluminum very light, and also allows more surface of the metal to get rid of heat fast. "

Read that and THINK about it. Wide molecules make for a greater surface area? DOH!

So you dont understand that article? Mike Larsen made up his credentials?

You would rather listen to your three sources?

Maybe Kyle's (Hard OCP) review of the HedgeHog was wrong?

Fine. Maybe you are more interested in appearing intelligent than presenting correct information.

[CU later]

Oh yea...I forgot....

You accuse me of being inept?

You are going to guys that mix cement for computer heatsink advice.

[Joe]

1. Yes I will listen to my sourcs cause I know 2 of them are paid to know it.

2. the guy who "mixes cement" designs and builds power systems for 15 million dollar Cement processing equiptment. I would hardly call that a "Mixing Cement" job. Hes actually more qualified in credentials then the Physics profs I know.

So Far, you are bout the only person to really question me, and you send one link to one article that presents an opposing view. I have 3 people who present a view that backs mine up, whom I know personally and know their credentials. THAT is the reason I dont hold much credit to the arguments.

The reason I posted your email is you were being a dick, and as I posted Liquid Radiations email to correct me on something, I posted yours.

No I am NOT perfect but I want REAL information oh how Cu is better then Al. in HSF situations. Not just hearsay. I am getting ( or trying ) to get some sort of formula or scientific explanation from one of the Physics buds I know to post.

Please get some REAL proof that I am incorrect, and I will gladly post the correct info.

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C-ya
Joe

[This message has been edited by Joe (edited 10-16-2000).]

[pandora]

Well my brother is a college metal work/chemistry lecturer and he said that alaminium is one of the best metals to disperse heat quickly

by the way everyone physics has nothing to do with metals physics is about trejectories velocities angles of incedence and crap like that (pretty much maths stuff)

[pandora]

copper is a good conducter of HEAT so its good if you want to transfer heat from one place to another a chead form of peltier its not good just for a heatsink

[gurglblAt]

Im using the hedgehog right now, with my p3-700 @ 819. I had to lap the bottom for it to start working nicely. I can only say from my own experience that it's working quite well. Probably 3-6C less than my FDP32. Of course I'm running it with the side panel off of the 'puter. I just ordered a 72W peltier from Peltec. Got a better fan for it (delta 38cfm). As long as I can dissipate the heat off the hot side, it's gonna ROCK!!

[CU later]

Here is another a review of the Hedgehog.

http://www.hexus.net/hh.shtml

And the [H]ard OCP review.
http://www.hardocp.com/reviews/cooli...hog/index.html

The Alpha's have some killer designs I am sure their people worked long and hard on, yet the butt ugly Hog is keeping up with them and often surpasing them.

No offense Gurglblat, they are so ugly that they're cool.

I try to keep an open mind, but I have yet to hear an argument or see any proof that emmisivity (sp?) overcomes thermal conductance.

[CU later]

Wow, I really should have used the Spell Checker....

[Joe]

This is the discussion I was hoping for, more different views and some other ideas.

I am still not 100% sure either way yet....

But thanks for all your views.

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C-ya
Joe

[RJ-45]

I would just like to point out that in CU Later's second post he didn't appear to do anything but reinforce what Joe has be saying all along that copper is better for conducting heat than dissipating heat which is why if you actually looked at his web site you would see that he and his staff point out many time that Cu is Better for h2o applications yet Ai is better for HSF cooling. I think Cu Later should think before he posts stupid replies and stop letting his emotions control his ability to communicate intelligently also as to some of the replies specifically the one stating that he had a Cu heatsink running at 103 that's not something to be proud of my Ai heatsink is rather small and have 2 fans on it and I rarely exceed 93f but I do think the hedgehog heatsink would work excellent as a watersink

[CU later]

i think maybe chill RJ-45 should maybe investigate the issue a little further and perhaps visit more than one web site for his information and maybe look into USING SOME PUNCTUATION!


I'm sorry , I couldn't resist.

Anyway I have been involved in this debate several times, on different boards.

Most recently in the HardOCP.com forums ( do a search for aluminum in the overclocking cooling section ).

For a while I was convinced that Aluminum would be better. Someone had posted a table with the radiating abilities of several metals, and Aluminum was signifigantly better.

Then I realized that most heat is removed through conduction. If the fan dies on your CPU it will overheat pretty quickly. If radiation were then main factor it would not skyrocket in temperature.

Okay, enough of this for now.
CU Later

[RJ-45]

for you information I've been looking into the properties of metals for quite some time now and have looked at a extremely large number of web sites on this. As for conduction your right it is important for a heatsink to have both conductive and radiant properties this is why we have copper embedded heatsinks. This allows for heat to be conducted to the Ai which then allows better dissipation.

I have have seen several reliable web sites (mostly ones run by people with a degree in this area of science)that have provided the thermal resistance of both Ai and Cu. All of these sites have show Cu to have a higher thermal conductivity than Ai but also have stated that Ai has more surface area and therefore has more surface area.

I a heatsink one of the critical factors is surface area. If a heatsink has a large surface area this will allow for better cooling simply by the natural flow of air (heat rise etc.)

this can explain the variations in results because if one person tests a copper heatsink in a case with many blow holes the results will vary from that of someone who tests that same heatsink in a case with no blow holes.

As far as a metals ability to radiate heat Ai will always have more surface area than Cu. The only way to increase the surface area of Cu (to the best of my Knowledge) would be to make some sort of microscopic grooves on all surfaces of a heatsink. Since this would be so expensive I believe the heatsink that would preform the best at a reasonable cost would be a Solid Copper heatsink with a vary thin layer of Ai over the solid copper heatsink. This would allow for the for minimum thermal resistance and maximum surface area.

[CU later]

Hey man..... surface area is not a set value for for each metal (or anything else).

It changes as the shape of the thing changes.

Two peices of copper that weigh the same can have totally different surface areas.

This kind of thing is pretty basic.

The hard part to grasp is the fact that in real world apps, radiation transfers much less heat than conduction.

Ok
CU later.

[Rhino]

Saw this post and I had to register. To all that say aluminum over Copper, you are correct. I am in the Air Force, and I will give you a few reasons for the above statement. 1- I have been in an Air Control Squadron. Mobile Tactics. Controlling Air Craft from the ground. Well the DOD had Engineers design heat decoys. (Bomb decoys not are Radars). (Thermal night vision etc..) Copper was found to be the best thing to use. It holds heat in for longer periods of time. These decoys are heated with a heat lamp type of bulb, of sorts. 2.- Nascar is also a good example, they make as many parts as they can for the motor out of Aluminum. Why you say Less heat. 3.- Back to Radars, on the back of the sail and on the electric motor that turns the sail, yes giant Aluminum heat sinks to keep it as cool as possible(see the decoys not the radar). At the same time. We all must realize that there are many different grades (Quality) of both aluminum and copper. But when measured equally Aluminum is the better of the two.

[CU later]

I agree....copper would be the best thing for that purpose (thermal decoy).

Why? Not because it "holds heat in" ,but because it will absorb a whole heck of a lot more heat than aluminum.

Copper is much more dense.

Yes aluminum would cool off quicker. One big reason is that it DID NOT ABSORB AS MUCH HEAT.

Another reason is that Aluminum will radiate heat slightly better than copper. This doesn't have as big of an effect as you think.

We are not talking about blocks of metal that have been heated before hand to serve as decoys.

We are not talking about car parts where strength and weight are a concern.

We are talking about metal blocks that have a constant heat source (CPU) and forced air conduction cooling (fan).

In this situation I still feel that copper is superior.

You want to conduct heat away from your CPU.
Copper is a better conductor of heat.

C U L8R

[ondaedg]

if only we had a heatsink of copper and aluminum using the exact same design to test the thoughts of everyone. The control factor would be of course equal surface area.

[CU later]

A good idea.

But even that would cause debate.

Copper would win and the aluminum crowd would claim that it only won because of the difference in density.

The two sinks with identical surface areas and shape would not weigh the same.

Copper is pretty hefty.

[schuss]

As far as i know, Copper a better conductor of heat between surfaces than Al, but between the surface and air, AL is better. I could be wrong, but I do know that aluminum is always used for quick dissipation of heat, not copper. It is true that it absorbs more, but it also retains it, so as the proc keeps running, the copper would hold in more and more heat, while the aluminum would be dissipating it into the air. I'm no expert by any means, but CU, you still haven't produced anything to back your shit up. I'm curious about this myself, so if you can show some hard data, it would be educating.

[phosphor]

Heat capacity and surface area are critical issues between these two elements.

Shuss is correct with the Cu retention of heat at the source. Think about it, why use copper pots and pans? Al will be better at this point. Another engineering point of view is that Al will create a thin layer of oxide on the surface that will still conduct heat. However, Cu oxide is another matter. Just go and get your hedgehog today, but in a humid, polluted climate over a period of 6-months you will wonder what that green crap is and why it is no longer cooling that effectively.

-phosphor

[CU later]

Schuss.... let me quote from that article ( you did read it, right?)

And keep in mind the author has a masters in engineering with emphasis on structure and heat transfer.

"Aluminum does not 'give up its heat' better than copper! Let me repeat this once more; aluminum does NOT 'give up its heat' better than copper. It is true that, in general, aluminum will radiate heat better than copper but radiation is such a miniscule part of heat transfer in a computer system as to be deemed completely inapplicable.

The physical action of conduction/convection relies solely on the two material's individual thermal conductivities, their proximity to each other, and their time in contact with each other. Thus, a pure copper heatsink will always outperform a heatsink of the exact same geometry of a pure aluminum heatsink assuming that both have the same contact with the heat source and the same rate of airflow over the surface. "

And Phosphur... I think you have proved MY point! We use copper in pots and pans because it transfers heat rapidly and evenly to the food. It does not hold it in. If oxidation were a big issue....there would be no copper pots and pans. Who wants their beanie weenies out of green icky pot?

I am not saying that copper kicks aluminums ass, mind you. It is only a little better, but it IS better.

Why does the hedgehog perform at the alphas level?

It has less fins per square inch.....so thats not it.......

The fins are actually inserted into the sink, where as the alphas are one solid peice so thats not it......

Less surface area.....that aint it.....

Average design.......

Hmmmm could it be because it's copper?????

[phosphor]

Cu later,

Perhaps you are correct with pure copper as a cooling source. However in real world applications of cooling, oxidation of pure copper is a bastard to control. That was my point with the hedgehog. The acid content in water is enough to change copper to its salts over time. Aluminium has better resistance to corrosion because of the hard, tough film of oxide on the surface. BTW, hard water is a killer of copper pots and pans.

Sooo, if you want a better cooler, use silver...

-phosphor

[Joe]

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C-ya
Joe - Owner/Editor
www.ProCooling.com
Where the Completely Addicted Come to Cool Off

Somebody set up us the bomb.

[Cryonosis]

if nobody else will say it this way then I will.

The reason that copper is not used in making heatsinks is due to it's wieght, since copper is so much heavier, to keep from cracking your CPU's core, the copper heatsink must be smaller than the Aluminum one, in essence making the copper heatsink less efficent due to it's reduced size/surface area.

there's my input,

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