does anyone know if liquid metal conductonaut is safe long term? i know it has to be copper heatsink only. i am thinking i am going to go balls out, watch videos, do it properly on cpu and gpu in fall 2022 when i go big on next gen build. its got to be what 3-4 celsius better than even TFX, which is like 7-8 celsius gain over mx-5. and if done right, conductonaut never needs to be replaced.
hmm... to be risky or not to be risky, that is the question...
Copper heatsink?
It's safe if you do some prep work.
First if you're applying it on a delidded IHS that will be re-lidded:
1) apply LM on the IHS, both above (if you are applying LM onto the heatsink), and under IHS (the part that will contact the die), normal procedure for any delid+relid so far.
2) Put the IHS in an oven (DO NOT PUT A CPU IN THE OVEN).
3) bake the IHS at 100C (212F) for about 2 hours.
4) Remove IHS, let it cool, wipe the LM off the IHS with a lint free wiper or coffee filter. Do not apply excessive pressure, just gently wipe the LM off but leave the silver stain behind.
You don't want "strange tiny particles" to come off the metal in the form of grit, those tiny particles will interfere with full contact.
5) Apply a new layer of LM both above and under the IHS, on top of the old silver stain layer. This will give very long term durability of LM on your IHS.
Set the IHS aside somewhere while you now work on the heatsink or block.
For heatsink/heat block surface, you need to do more work.
First get some 1500 grit sandpaper.
Then carefully wipe the entire heatsink/heatblock surface with the sandpaper. You are not trying to flatten or fix any curvature imperfections (if you want to do that you're on your own with proper sanding methods). You're only just roughening up the surface to give the LM something to adhere to under pressure.
Once you buff the surface with 1500 grit, clean it fully with a lint free cloth or coffee filter.
Then apply your LM to the surface.
If you aren't using an IHS, you can skip this obviously.
Now, the long boring part.
Take about 15 minutes and carefully wipe gently, the LM around with a lint free swab. Lint free lip gloss applicators are perfect for this.
It's very important NOT to apply any downwards pressure. You again don't want tiny particles of metal grit getting scooped from the little micro-crevices you created with the sandpaper, and as you know, copper is a rather soft metal, as far as metals go. Just let gravity do the work.
After about 10 minutes of wiping and spreading the LM all around repeatedly, you're going to start noticing the LM getting much less runny and starting to feel 'thicker', almost like an extremely runny thermal paste. That's exactly what you want. Because it means some of the gallium is starting to get absorbed into the micro-crevices you made with the sandpaper.
So spend about 15 minutes wiping it like this. Make sure the surface does not feel gritty when wiping with the applicator. If it feels gritty, you need to start over. Not only does doing all of this work help start immediate absorption of some of the gallium part of the LM into the copper (or nickel plating), but it also helps keep the LM from shifting around under pressure. LM really likes rough surfaces. You'll notice that if you take a ball of LM and try to 'spread' it on a mirror finish copper or nickel plating, it won't want to spread at all. It just wants to stick to itself. That's because the mirror surface is giving extremely poor grip and adhesion to the LM. These surfaces also tend to have the most degradation of LM quickly as well. Now if you do the same on a 1500 grit buffed surface, you will see the LM spreads almost instantly. That's because of the grip from the micro-crevices which helps give the LM something to stick to. This becomes very important when you compress the surfaces together during IHS/heatsink mounting.
After about 15 minutes, now apply a new layer of LM on top of the old layer (don't remove the old layer). A drop or two will do (but make sure you apply the new fresh layer on top).
Then spread it normally without another long spread, like you're used to doing, then apply LM to the CPU (or GPU) core, attach the IHS (if applicable), then apply the heatsink or block on top.
This will give very long durability over time.
