Aluminum vs Copper

[Tuff]

Before anyone shouts out...use the Search...I did and there is WAY to many to go through to find the answer I need.

I made a waterblock today out of Aluminum.

The Question I have...How much of a diffence in Temp would I get if I constructed the exact same design out of Copper?

The design is a channel maze.

Water feeds in through the center and moves around the block in a circle through drilled channels then exits out the side.

AS it sits right now...I get 30-32 at idle

Tuff

[Cathar]

Depends on the exact design, but anywhere from 3-6C better in general by using copper instead of aluminium.

[Tuff]

Wow..that much...I just resat the block ...had to change a barb location...I will see if that has made a diff or not.

Tuff

[bigben2k]

It does depend on the design.

Also, because copper is better at allowing heat to travel through it, the design needs to be altered, typically by reducing the baseplate thickness. Doing that to an Alu block would result in worse temps, assuming that the bp thickness is already optimized/ideal.

[Tuff]

Hmm..Still get 30 Deg C...I guess thats good enough...cannot seem to find Copper blocks here and my 1/4 inch copper flat bar is still at the machinist.

Breaking into the 20 Deg c range would be cool though

Tuff

[chewyboy]

one thing i've learned recently also is the type of al you are using also. depending on what you have, and how it was treated after you finished your block you may get that now but 2 months down the road you may not have any al left inside because of corrosion.

[Tuff]

Good news...AS3 has settled in and now I run 28 Deg C


Water in Res stays cool to the touch.

Tuff

[j813]

Originally posted by bigben2k
It does depend on the design.

Also, because copper is better at allowing heat to travel through it, the design needs to be altered, typically by reducing the baseplate thickness. Doing that to an Alu block would result in worse temps, assuming that the bp thickness is already optimized/ideal.

Can u explain "Alum Block would result in worse temps" in a more simple manner?

[j813]

Originally posted by chewyboy
one thing i've learned recently also is the type of al you are using also. depending on what you have, and how it was treated after you finished your block you may get that now but 2 months down the road you may not have any al left inside because of corrosion.

Does this really mean that Aluminum are corrosive or would gradually decrease?
Other comments out there?

[bigben2k]

Originally posted by j813
Can u explain "Alum Block would result in worse temps" in a more simple manner?

Hum... Ok, let's try this:

The optimal performance that can be reached with copper, is better than the optimal performance that can be reached with Aluminium.

If you understand the dynamics of what goes into designing a waterblock, or you have experience in trying out multiple variations of a design, in Alu and in Copper, then the above should be clear.

[redleader]

Simpler:

Copper is better at moving heat. Thus you need less copper in the base plate then aluminum. So make an aluminum base plate thicker to compensate.

Alumium is highly corrosive (explosive too!). Fortunately it forms a thin layer of alumium oxide that keeps it from burning/rusting away. However if you mix it with copper, you will get corrosion as the two metals slowly react each other away.

[j813]

Originally posted by redleader
Simpler:

Copper is better at moving heat. Thus you need less copper in the base plate then aluminum. So make an aluminum base plate thicker to compensate.

Alumium is highly corrosive (explosive too!). Fortunately it forms a thin layer of alumium oxide that keeps it from burning/rusting away. However if you mix it with copper, you will get corrosion as the two metals slowly react each other away.

EXPLOSIVE? Why & How?
I tried to put my Alu fins & Copper tubed Radiator under water & abt 10mins after there's the white salty particles obviously that's the corrosion right?
But Explosive reaction? when & how wud it happen?

Just got the CNC made maze1 made from Alum w/ a 2mm base plate & after reading this new messages I might make a suicide trial w/ my Duron.
Will it survive my test? Hope it wud!
TY

[Balinju]

nono your duron is safe if you have no copper in your rig.

i think by saying explosive is a little bit exagerated. imagine putting a piece of sodium in water or a piece of pottassium. that would be an explosive reaction, but i think pure al without any alO would not explode in water, your block forms a layer of alO exectly as you are cutting it, and in that way, it would not corrode so you are safe

[Alchemy]

Originally posted by redleader
Alumium is highly corrosive (explosive too!). Fortunately it forms a thin layer of alumium oxide that keeps it from burning/rusting away. However if you mix it with copper, you will get corrosion as the two metals slowly react each other away.

Sigh.

No, no, sort of, and no.

Aluminum is highly non-corrosive and does not react violently with any but the worst oxidizers. It's commonly mixed with copper and other metals to strengthen or soften it.

Aluminum forms a thin layer of aluminum oxide which protects it, unlike steel, which forms thick and brittle layers of iron oxide (rust) that weaken it. If you scrape off a layer of aluminum oxide, it just forms another layer.

Aluminum will only burn under high-pressure oxygen - at least 25 - 50psi and pure O2. It's an issue with people handling compressed oxygen (FDA recommends not using Al regulators under certain conditions) but it's a very special condition. Damn near *everything* burns under pure, high-pressure oxygen!

Metallic copper and aluminum DO NOT REACT! They're both very similar metals - there's no mechanism for a mixture of metals to "eat each other away" with.

http://www.webelements.com/webelemen...inium/key.html

Alchemy

[jaydee]

Originally posted by Alchemy


Metallic copper and aluminum DO NOT REACT! They're both very similar metals - there's no mechanism for a mixture of metals to "eat each other away" with.

http://www.webelements.com/webelemen...inium/key.html

Alchemy

Metalic copper as in C110? So what causes the battery effect then?

[sevisehda]

Actually copper is quite reactive. Its forms such a thin layer because it reacts with the 02 in the atmosphere so fast.

Aluminum powder + Rubber is highly explosive, probly why they use it in rocket fuel.

Have we not heard of the battery effect?

[MadDogMe]

Metalic copper as in C110? So what causes the battery effect then?

Water?, a third element. The two by themselves are'nt reactive AFAIK, ie; placing an Alu block onto a Copper block(in a dry atmosphere) will not cause a 'reaction' AFAIK. I think peoples definitions of 'reaction' are off a bit...

Aluminium powder is'nt 'explosive' let alone highly. Aluminium powder is combustable (but then most things are when powdered or at the right temp ), it does burn hot once ignited though and is used in some thermite 'bombs' which is maybe where the 'explosive' idea came from?...

[#Rotor]

please, just let's steer clear from any BOOOM talking....

THEY.... are watching us, and the last thing I want to become is a crazy hacking slashing overclocking "BOMB-builder"...

copper and aluminum can be good buddies, all together... if portability is the biggest issue, a hybrid system is advantageous. Aluminum sports a far superior performance curve, if it is shown against weight, compared to that of copper.

[bigben2k]

Alchemy was trying to correct redleader: copper does not react chemically with Aluminium. Alu will corrode, but protect itself, if left alone. Copper will corrode, similarly to steel, until there's nothing left, I believe. This is a very long process, but the mere presence of aluminium (in electrical contact in the water) will accelerate the process: that's the battery effect.

Alu is not explosive

[jaydee]

Originally posted by MadDogMe
Water?, a third element. The two by themselves are'nt reactive AFAIK, ie; placing an Alu block onto a Copper block(in a dry atmosphere) will not cause a 'reaction' AFAIK. I think peoples definitions of 'reaction' are off a bit...

Agreed. Ok, so it still stands not to use bear AL and Copper/Brass together in a water cooling system. I find that the two actually touching is far more 'lethal" than having the water connect the two (i.e. al block and a brass rad). I ran an AL block with a acrylic top and brass barbs (keeps the metal from touching) for several months with a brass rad with no visable effect on the block, but I also ran a AL block with an AL top and brass barbs in it and about a month later took it apart to find the AL top and base just about eaten through.

So would one expect the two metals in direct contact with each other with water flowing over them to be considerably worst than a setup with indirect contact between the metals? And is it just a myth that a brass rad and AL block would even cause the battery effect being they are not in contact with eachother???

[Alchemy]

Originally posted by MadDogMe
Water?, a third element. The two by themselves are'nt reactive AFAIK, ie; placing an Alu block onto a Copper block(in a dry atmosphere) will not cause a 'reaction' AFAIK. I think peoples definitions of 'reaction' are off a bit...

Aluminium powder is'nt 'explosive' let alone highly. Aluminium powder is combustable (but then most things are when powdered or at the right temp ), it does burn hot once ignited though and is used in some thermite 'bombs' which is maybe where the 'explosive' idea came from?...

Thanks. This was what I was trying to get across.

Metals such as these don't just "eat each other away." They can be made into galvanic cells, in which electrochemical potential will cause electron movement and corrosion or electrochemical plating. But it's the electrolyte (the impure water) that makes this possible. This happens to *all* metals.

Alchemy

[iggiebee]

Putting chemical incompatibilities aside the following should hold true: "copper is better at absorbing heat than aluminum, while aluminum is better at shedding heat than copper", or so I've heard.

[Alchemy]

::strangles someone::

[Since87]

Originally posted by iggiebee
Putting chemical incompatibilities aside the following should hold true: "copper is better at absorbing heat than aluminum, while aluminum is better at shedding heat than copper", or so I've heard.

AAAAAAaaaaaaaaahhhhh!!!

Quick somebody get me a wooden stake!!!

[jaydee]

Originally posted by Since87
AAAAAAaaaaaaaaahhhhh!!!

Quick somebody get me a wooden stake!!!

I got some wood, gas, and matches.