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View Full Version : Galvanic corrosion.... Time to beat the dead horse.



Tt Enthusiasts
09-24-2012, 09:07 AM
As many of you know there is a widespread fear of Galvanic corrosion when using ALU parts in a LCS.

I have seen many of the same pics all of you have, but i feel like there is a lack of understanding as to what causes Galvanic corrosion and how it affects you the LCS enthusiasts.

So feel free to post your thoughts, evidence and discuss but please no flaming, bashing or otherwise talking down another person just because you dont agree with them.... these kinds of posts will be removed.

from my experience I as well as the rest of you do not like to use ALU in my loop simply because it has been bashed into my skull on many enthusiasts forums that it is some kind of evil and the corrosion trolls will get in my systems and eat my parts....

now after testing for quite some time with properly maintained loops I have yet to ever see any signs of galvanic corrosion....

Now I must ask if you keep on top of your loop and drain/refill and refresh the liquid supply do you need to worry?

Seems like most cases I have seen of galvanic corrosion were cases where it appeared like simple maintenance was never performed and the liquid was never really changed out, or even worse distilled water was used with no sort of corrosion inhibitor.

Please feel free to discuss intelligently below.

OldChap
09-24-2012, 10:30 AM
Given that distilled water will not stay that way for long in any metallic environment, what are you suggesting for the " service period" of any maintenance regime?

I use a plain old painted steel pump (not quite your material of choice but nonetheless dissimilar metals) on the MOAF system and therefore decided that using an automotive "Anti-freeze" additive (around 10%) would be beneficial even if it may detract from the absolute maximum performance of the cooling effect. This I expect to replace the coolant every 2 years..... but this figure is not scientifically derived. Do you have a method of projecting a time period beyond which the efficacy of either clean distilled water or additives can be determined to be detrimental to the loop?

Are you proposing to use any additive?

BeepBeep2
09-24-2012, 10:36 AM
Most of the time, guys run without a corrosion inhibitor because they keep with brass/copper metal loops.
AFAIK it has been shown that glycol based coolants/additives have worse thermal properties of water and reduce the amount of cooling capacity a noticeable amount.

Furthermore, aluminum is inferior to copper as far as heat conductivity and this is XtremeSystems :p:

One of my HeatKiller blocks exhibited signs of galvanic corrosion and very heavy oxidation after 1 year in a loop with distilled + copper sulfate II. I think those blocks use impure copper though, many people have problems with them.

Tt Enthusiasts
09-24-2012, 11:03 AM
Given that distilled water will not stay that way for long in any metallic environment, what are you suggesting for the " service period" of any maintenance regime?

I use a plain old painted steel pump (not quite your material of choice but nonetheless dissimilar metals) on the MOAF system and therefore decided that using an automotive "Anti-freeze" additive (around 10%) would be beneficial even if it may detract from the absolute maximum performance of the cooling effect. This I expect to replace the coolant every 2 years..... but this figure is not scientifically derived. Do you have a method of projecting a time period beyond which the efficacy of either clean distilled water or additives can be determined to be detrimental to the loop?

Are you proposing to use any additive?


The issue here is why I started this thread...

There is very little factual information on the subject and many see a picture of a horribly corroded interior of blocks or loop and automatically jump on the Galvanic corrosion witch hunt...

or even worse making wild assumptions...

When in reality there are so many variables from loop to loop that can cause issues. Like I said in my original post I dont like mixing metals but more importantly I wanted to see what factual or proven testing or information has been done so at least its in one place so someone can avoid the pitfalls or mistakes that others have seen or experienced.

I dont have an additive of choice but in my loops I usually drain them every 6 months and refill. I have a drain line that expedites the process and from start to finish it is about 18-20 minute process including running fresh water thru the loop for 4 minutes which is something I personally do just to see if anything flushes out as we all know we cannot really see inside our blocks or rads.

Tt Enthusiasts
09-24-2012, 11:05 AM
Most of the time, guys run without a corrosion inhibitor because they keep with brass/copper metal loops.
AFAIK it has been shown that glycol based coolants/additives have worse thermal properties of water and reduce the amount of cooling capacity a noticeable amount.

Furthermore, aluminum is inferior to copper as far as heat conductivity and this is XtremeSystems :p:

One of my HeatKiller blocks exhibited signs of galvanic corrosion and very heavy oxidation after 1 year in a loop with distilled + copper sulfate II. I think those blocks use impure copper though, many people have problems with them.

This kind of goes inline with what I was saying as there are so many variables with so many parts if you know what I mean.... thats why I want to see what we can find out about this actual phenomenon and what we can do to avoid it. no matter how you look at it some parts including pumps have ALU parts in them or other metals so figuring out what works best could help alot.

Honestly if anyone is willing to do some honest testing I will be happy to try and get some of our bigwater series radiators which have ALU to help support the testing cause.

StAndrew
09-26-2012, 03:43 PM
Your logic is sound but its still a taboo among "enthusiasts." Switech's rad/pump kits are more expensive but if I were to get a simple CPU loop, that would be my choice.

Here's my opinion: Last time you looked for input from this crowd i believe it was on case design; you were pretty much blasted with criticism. I admired your poise under fire but I have yet to see TT make that quantum leap away from "mainstream cheap."

I really believe a company with the resources of TT can really delve into the ever elusive "high quality affordable" market (which is where I think you were looking to go with the case thread). Sure Cu is more expensive than Al but I think quality will always be my primary choice. You cant skimp on performance/function for price. TT needs to make a decision to take the next step or join Asetek, Corsair, Coolit, etc... as a manufacture of "mainstream cheap" watercooling.

If TT choose the later, you may as well delete your account and move on. Cheap isnt well appreciated... :shrug: Again, just my opinion.

Sparky
09-26-2012, 04:09 PM
Given that mixed metals bring about the very real risk of corrosion, and brass/copper have the better thermal properties, I see very little reason to even entertain the thought of aluminum in a loop. What's the point? Save a couple bucks? But then I'm having to buy corrosion inhibitors and change it much more often, while with an all bras/copper loop I can run over a year with nothing but a $1 bottle of distilled + a biocide. Doesn't seem to be much benefit and definitely an increased risk. All brass/copper is practically foolproof.

Swiftech tried a plated aluminum top on a block and that was a miserable failure. They learned and haven't touched that idea since.

BeepBeep2
09-30-2012, 02:50 PM
Given that mixed metals bring about the very real risk of corrosion, and brass/copper have the better thermal properties, I see very little reason to even entertain the thought of aluminum in a loop. What's the point? Save a couple bucks? But then I'm having to buy corrosion inhibitors and change it much more often, while with an all bras/copper loop I can run over a year with nothing but a $1 bottle of distilled + a biocide. Doesn't seem to be much benefit and definitely an increased risk. All brass/copper is practically foolproof.

Swiftech tried a plated aluminum top on a block and that was a miserable failure. They learned and haven't touched that idea since.
I thought aluminum has better thermal properties than brass?
But brass is used because copper is too expensive.
Aluminum is more lightweight too, much more than copper.

To be honest, I don't think mixing nickel, silver, brass and copper in the same loop is good either but people do it all the time.

Tt Enthusiasts
10-03-2012, 09:54 AM
Your logic is sound but its still a taboo among "enthusiasts." Switech's rad/pump kits are more expensive but if I were to get a simple CPU loop, that would be my choice.

Here's my opinion: Last time you looked for input from this crowd i believe it was on case design; you were pretty much blasted with criticism. I admired your poise under fire but I have yet to see TT make that quantum leap away from "mainstream cheap."

I really believe a company with the resources of TT can really delve into the ever elusive "high quality affordable" market (which is where I think you were looking to go with the case thread). Sure Cu is more expensive than Al but I think quality will always be my primary choice. You cant skimp on performance/function for price. TT needs to make a decision to take the next step or join Asetek, Corsair, Coolit, etc... as a manufacture of "mainstream cheap" watercooling.

If TT choose the later, you may as well delete your account and move on. Cheap isnt well appreciated... :shrug: Again, just my opinion.

all of the feedback I get is not lost.... it is simply something that helps shape my direction and how i help direct future product development.

at the end of the day like any business there is a roadmap and many products are planned long ahead which means ideas I have now may not be seen for a short while.

Sparky
10-05-2012, 02:19 PM
I thought aluminum has better thermal properties than brass?
But brass is used because copper is too expensive.
Aluminum is more lightweight too, much more than copper.

To be honest, I don't think mixing nickel, silver, brass and copper in the same loop is good either but people do it all the time.

No, aluminum doesn't conduct heat as well as copper or brass does. It is lighter and cheaper though.

cdawall
10-14-2012, 09:04 PM
Aluminum+Copper/brass has existed in cars for decades. Galvanic corrosion happens however with a mild glycol additive doesn't happen anywhere near as fast. The performance difference in my personal experience isn't much. I currently run DEX-COOL 25%/Purified water 75% in my loop and for 2 years have no changed the fluid (all brass/copper loop) no mess, no gook, no nothing in my loop. I will continue to run a loop with glycol in it. Works very well as far as I am concerned.

demonkevy666
11-01-2012, 07:51 AM
I just want to know about something.

is the aluminum welded with aluminum, or its is solder with some special solder?

last time I check you can't just solder together aluminum with regular solder.

Shocker003
11-01-2012, 08:35 AM
Well i have never tried out combination of copper and alu willingly in my loop.
I think Coolermaster aquagate had it but the setup died after i changed the alu rad due to my fear of the so called Galva-:banana::banana::banana::banana: corrosion.
Why canĀ“t Tt offer Alu rads and alu water blocks. This way we can have a pure alu setup in our loops.

Conumdrum
11-30-2012, 03:44 PM
Al waterblocks suck for heat transfer. That's why. That's why they haven't been used for EONS.

zanzabar
11-30-2012, 04:09 PM
Al waterblocks suck for heat transfer. That's why. That's why they haven't been used for EONS.

you only need a copper base to contact the cpu, you could have solid aluminum around it (not a copper base with liquid a copper base core with aluminum poured around it) and it should work fine (though not as good as all copper,) it just seams better to keep it all copper/brass/nickle, or all aluminum. the main problem with the TT kits i though was that they had copper and aluminum touching (or very close) like swiftech did with the gtx or foxconn did with the blackops, and we all have seen what those did.



Aluminum+Copper/brass has existed in cars for decades. Galvanic corrosion happens however with a mild glycol additive doesn't happen anywhere near as fast. The performance difference in my personal experience isn't much. I currently run DEX-COOL 25%/Purified water 75% in my loop and for 2 years have no changed the fluid (all brass/copper loop) no mess, no gook, no nothing in my loop. I will continue to run a loop with glycol in it. Works very well as far as I am concerned.

car water pumps die all of the time (normally a hard steel impeller that degrades but not from rust,) and so do the rads from getting clogged up. the cars that have iron blocks with aluminum heads also generally use iron mixed with tin, titanium, manganese, and chromium among other trace metals so they get along with aluminum better than copper or brass would. cars also do not have to worry much about efficiency so everything is treated, but liquid cooling blocks and rads are normally raw or nickle plated and that dose not stop corrosion.

cdawall
11-30-2012, 10:56 PM
car water pumps die all of the time (normally a hard steel impeller that degrades but not from rust,) and so do the rads from getting clogged up. the cars that have iron blocks with aluminum heads also generally use iron mixed with tin, titanium, manganese, and chromium among other trace metals so they get along with aluminum better than copper or brass would. cars also do not have to worry much about efficiency so everything is treated, but liquid cooling blocks and rads are normally raw or nickle plated and that dose not stop corrosion.

As far as the pump goes they do die all the time, but not normally until 10 years have passed if not more. Even on my iron/iron 4.0L I-6 in my Jeep from the factory was aluminum which had obvious corrosion, but also lasted almost 20 years. Galvanic corrosion happens, but like I said glycol does slow it down.

Sparky
12-10-2012, 04:01 PM
I still fail to see the reason to even bother with glycol/mixed metals/risks/etc when it is so easily avoided. You basically have two ways - easy and low risk, or complex and higher risk. What's the point in that?