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ArcticMyst Security by Avery

Heat sinking (what kind of metal to use?)






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Jan 7, 2007
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Depends on what you have to machine to fit. Copper, Aluminum and Silver are all good. Machine for good fit and use Arctic5 to fill in the gaps.

Mike
 
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Jul 16, 2008
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Yeah, copper seems like a very good conductor of heat, as evident in the finger burn you get while soldiering copper wire.

I once thought that, in a pinch, it would be easy to tightly wind fine copper wire around the Aixis
module, to achieve a desired taper for a tight fit inside the host tube..................................using
Arctic5 ^^^to fill in the gaps.
 

UMO

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Aluminum if size permits because it is cheaper and lighter than copper and silver.
 
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It depends on a few things. If your heat sink is going to be just a 'block' of metal, aluminum would be best. If you can get a heat sink with a lot of very thin fins on it, with a lot of access to air, then copper is the best.

The problem with copper is that it has a huge capacitance for heat. If it is shaped as just a block, it will just keep sucking in the heat and store it, getting hotter and hotter without dispersing the heat to the air. This is why you have to have many fins with copper, in order to transfer it into the air.

With aluminum, it holds much less heat than copper, which is a good thing in the type of configurations that we usually use. It sucks away the heat and quickly radiates it into the air without storing a whole bunch, even when shaped as a 'block' of metal.

As far as silver, I really don't know enough about it to comment, but it sounds expensive anyway  ;D
 
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Silver would be the best heatsink...

But... it would cost a fortune to get a block of pure silver to use as a heatsink :) The benefits of Silver really don't justify the MASSIVE price increase over aluminium :)
 

diachi

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Diamond ;D

Don't look at me like that, its a better thermal conductor than silver :D
 

Switch

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Diachi said:
Diamond  ;D

Don't look at me like that, its a better thermal conductor than silver  :D

Yea I know, it's like 20 times better than aluminum , but a whole s%#t load more expensive.And unmachineable.Who would use diamond for heatsinking? :-/
 
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Well not all diamonds look like the ones you see in jewelery, uncut they look like an ordinary rock. Plus there are many diff grades, lab ones made for industrial purposes don't look particularly nice either, just the problem would manufacturing a lab diamond of sufficient size to be shaped for a heatsink, if you arranged a bunch of diamonds and connected them with lets say a thermal epoxy to then machine into a heatsink you would negate pretty much any added benefit of the diamonds superior heat conductivity due to the epoxy adding an insulating effect. Unless you arranged the diamonds in a way that they would connect them to the heatsource like the cell's in an orange are connected when it is cut at its equator, but that a whole other story.

Oh yeah also the price would be a b*tch

brtaman
 
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Just thought I'd throw in my 2 pence worth from a PC overclockers perspective.

By the way, all my comments are from a practical perspective.

So, metal is the only way to go, and not something fancy like Silver. Only Aluminium or Copper.

Copper is all nice when talked about, but in practice means very little.

Aluminium is cheap as chips to buy these days and easy to machine aswell.

The most effective and efficient PC coolers around by far are solely alumimium based and we're talking about heat removal several times more intense than you'd ever experience with lasers.

Alternatively, if aesthetics aren't important and you're mainly developing or experimenting, then why not consider forgeting the heatsink and just go with old-fashioned air-power.

Get your hands on a high-flow case fan from your hardware store or a spare one from an old PC or something, and make a home-made duct to channel the flow and point it at your module. This would be more effective than any heatsink alone.

jobsagoodun!
 
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Being a former overclocker as well. I have found in my extensive use of various heastinks that copper is in fact much better at getting the heat off a CPU die than alu. In air cooling as well as water cooling and phase change cooling, copper just has the ability to soak up the heat faster than aluminum, while alu might be better at releasing that energy into the air surrounding it, the high CFM fans, flowing water or liquid gas MORE than make up for this with copper.

However in the case of lasers there is no active cooling, it is passive therefore the alu is possibly the better choice.

Based on what experiences (specific heatsink comparisons) with CPU cooling have you determined the superiority of the alu heatsink?


brtaman
 

Switch

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ok so , it's aluminium , copper, silver and then diamond and nothing inbetween? :-?
 
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Nothing us mortals can get our hands on, I am sure that the governments and or top scientific institution have alloys that provide improved heat transfer capabilities. But for us hobby folk thats about it.

Why though? Whats wrong with alu or cu?


brtaman
 
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You could go gold or platinum. Cheaper than diamond and possibly better than silver, aluminum, copper since they won't tarnish or oxidize. That would be in-between.
 




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