Thermal Adhesives

[Jig]

Does anyone know if Loctite thermal adhesive is any good, how much, and how compared to TH silver adhesive ?

Specifically loctite 383/384

[Richard]

Thermal Conductivity of Loctite adhesive 0.757 W/mK


Thermal Conductivity of Arctic Silver adhesive 7.5 W/m°K

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I got those numbers from Loctite's website and Arctic Silver's website.

In essence, the Loctite adhesive has properties that would rank it with your standard silicone based compounds. Whereas, the Arctic Silver adhesive is in a class by itself. Granted, you could probably take these numbers with a grain of salt, because you should only be using a very small amount.

In an ideal situation the mating surfaces would be lapped smooth to remove as many defects as possible, and then a razor thin application of thermal compound separating the two. Then, I'd use just enough bonding material to hold the surfaces together.

[Iron Prophet]

Ready to get into another debate about how to apply AS2. And how thick it should be

[Richard]

http://www.arcticsilver.com/arctic_silver_instructions.htm

[Colin]

Artic Silver epoxy is the way to go. I used it today to attach heatsinks to the mosfets and clock gen on my new motherboard and a heatsink on my video card.

[Iron Prophet]

and what temps are you running at

[Jig]

Richard, I saw the same #s on both sites as well. The lil 0 after the m for the artic silver had me wondering if the spec was different between the 2 ratings.

[ZX-Tex]

Funny you ask... I JUST used the Loctite thermal epoxy on a homemeade heatsink. It was free, leftover expired stock from work and did not cost me anything. It worked.

As mentioned above the Arctic silver claims a much higher thermal conductivity. I ran some numbers. Even with a very thin layer, like .005", at 100W of heat, the differences in thermal conductivity are significant. If it is as good as it says, the Arctic Silver would result in a delta t (engineering talk) of 2-5 degrees cooler than the Loctite stuff. What this means is your CPU would run 2-5 degrees C cooler with the Arctic Silver all else being equal.

So, the short answer is use the Arctic Silver. In fact, I just ordered some of their thermal paste. Right now I am using the cheapo Radio Shack thermal paste.

[BillA]

not that its so big a deal, but for Loctite 3873 the thermal conductivity is given as 1.65W/m-K on their website (http://www.loctite.com/new/pr_3873.html).
(Loctite has MANY products)

I would not be unduly influenced by "factory specs", numerous attempts to quantify the performance differences between goops have shown only the smallest of real world differences despite much larger "spec" divergences
(no doubt also related to the testing equip and procedures)

be cool