I got this material from the bargain bin at a local e-surplus place a few years ago and forgot about it until now.
When I got it , a casual glance at the open sample and I assumed it was silicone pad with fiberglass reinforcing. At a dollar for something like 100 TO-220 size pads it seemed worth a try.
Opening it up to use tonight, some of the pieces seem to be sweating something oily. A little tacky they will stick to the transistor or heatsink but pull off easily. It's not adhesive.
Holding them at the edge with needle-nose pliers as tweezers to place them will squish the edge , sometimes tearing the material a bit.
Fixing a heatsink, a screw can be pushed through easily (I know that's not the prescribed method. Just checking it out) . Tightening it down, the pad squeezes out a little like putty but does have some kind of fibre inside. At the top edge nearest the screw where it gets tightest , the material shears.
Is there such a thing as a thermal putty pad like this or is it a cheap silicone pad that is breaking down? Anybody know what it is?
Thanks
When I got it , a casual glance at the open sample and I assumed it was silicone pad with fiberglass reinforcing. At a dollar for something like 100 TO-220 size pads it seemed worth a try.
Opening it up to use tonight, some of the pieces seem to be sweating something oily. A little tacky they will stick to the transistor or heatsink but pull off easily. It's not adhesive.
Holding them at the edge with needle-nose pliers as tweezers to place them will squish the edge , sometimes tearing the material a bit.
Fixing a heatsink, a screw can be pushed through easily (I know that's not the prescribed method. Just checking it out) . Tightening it down, the pad squeezes out a little like putty but does have some kind of fibre inside. At the top edge nearest the screw where it gets tightest , the material shears.
Is there such a thing as a thermal putty pad like this or is it a cheap silicone pad that is breaking down? Anybody know what it is?
Thanks
I have similar pads but larger in size apeox 100x100mm.
I think it is a fiberglass.mesh onto which a silicone oil/silica grains is pressed together.
If I push the edges it breaks apaart and the mesh is visible.
It is very mallable albeit sensitive at the edges. Slightly tacky as you describe it.
The one I have have a thermal.conductivity of 5W/mK which is well above what one would expect of a silicone elastomer pad simply because the later is rubber and hence less thermally conductive filler.
The only disadvantagas as I see it is that it might age over time and either harden/crack or flow undee.pressure. It feels a bit elastic. But on the other hand I doubt it is possible to produce that large pressuee on semiconsuctor capsules.
I think it is a fiberglass.mesh onto which a silicone oil/silica grains is pressed together.
If I push the edges it breaks apaart and the mesh is visible.
It is very mallable albeit sensitive at the edges. Slightly tacky as you describe it.
The one I have have a thermal.conductivity of 5W/mK which is well above what one would expect of a silicone elastomer pad simply because the later is rubber and hence less thermally conductive filler.
The only disadvantagas as I see it is that it might age over time and either harden/crack or flow undee.pressure. It feels a bit elastic. But on the other hand I doubt it is possible to produce that large pressuee on semiconsuctor capsules.
Do you know how it's ordinarily meant to be applied?
With no hole for screw, and also the fact it doesn't compress evenly across its surface I'm guessing it's meant to be used in something like a clip on sink where the pressure is applied more in the centre of the heatsink body than one with a screw close to one end.
Do you by any chance have a commercial name for it that I can look up?
Thanks
With no hole for screw, and also the fact it doesn't compress evenly across its surface I'm guessing it's meant to be used in something like a clip on sink where the pressure is applied more in the centre of the heatsink body than one with a screw close to one end.
Do you by any chance have a commercial name for it that I can look up?
Thanks