Heat Sink Glue-Which?

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You need a thermally conductive glue......

Look or search for Loctite "Output 384" ( that's the one I use, and the only one I know of right away.....)
It's a 2 part epoxy like glue, the glue in a large tube and a liquid accelerator... just follow the instructions carefully!
looks like the old white Araldite Rapide
 
Hi,
adhesive pad is far too thick for good thermal transfer.
even the glue on Sellotape is a bit on the thick side.

Cyanoacrylate (instant glue) is very thin when the too surfaces are genuinely flat. The thermal resistance of a very thin glued joint should be acceptable. If the joint faces are not quite flat then sufficient glue to exclude the air will perform adequately well.
But, squeeze the glue out with good finger pressure (watch static).
 
WE had this discussion in Class D re adding a small sink to the T-amp chips; opinion was Superglue (cyanoacrylates) has too low a temperature limit (though this seems to vary with brand, so YMMV).

I used (on recommendation) JBWeld, a filled epoxy claimed to stand red heat; does the job.

I'd certainly expect the thermal epoxies sold for the purpose to be better, but they're hellish expensive.

Like any other TIM, the thinner the bond, the better the heat transfer.
 
All epoxies will gell and pry off at 200Deg C.

Epoxies has structural strength and Superglue does not, they will shear the second there is impact or leverage, also the texture on most chips will leave small gaps which limits proper thermal transfer. The best glue based product is from Loctite, they have a two part activator type glue that is fast and effective.

Another option for low heat (up to 120Deg C) and non-permanent applications is thermal tapes. The best ones are from Chomerics, their silver impregnanted acrylique aluminium meshed double sided tapes are the best and the regular aluminium foil or silicone based transfer tapes found on most PC based application

I stuck a heatsink on the TA2024 with just the regular AL foil transfer tape, it has more than enough holding strength.
An externally hosted image should be here but it was not working when we last tested it.
 
Hi,
what's all this talk of 100+ degC?

If Tc is that hot the chip is beyond starting to struggle.

If I were adding a heatsink to an overheating chip then I would be looking for Tc<70degC and preferably <50degC.
Cyanoacrylate easily survives these temperatures.

And the low viscosity also fills all the crevices and undulations.
 
Well... I've used the Loctite "Output 384" for several years now. Made for the purpose of glueing heatsinks and the likes, bonds well if instructions are followed, and prys off *fairly* easy by using a knife edge or something...

Costly - prb'ly is- I use it professionally, so I don't pay from my own smallish heap of doe...

The PC crowd hails the Arctic silver stuff, but I have never used it....

Everyone to his own taste , I guess.......
 
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