Heatsink grease

[Andrew W. Macfadyen]

Problem with black paint is not only the thermal conductivity of the paint will be
lower than aluminium but it also  you are introducing another set of film
coefficients.

Joe Boucher wrote:

> > From: Chris Conlon <synchris at ricochet.net>
> > Date: Wed, 19 Aug 1998 00:16:08 -0400
> > Subject: RE: Heatsink grease
> >
> > Apologies for the vaguely-efi content,
> >
> > There are several greases designed to increase heat flow between (say)
> > a transistor and a heatsink; are there compounds to increase heat flow
> > between a heat sink and air? I know you can paint it black, but I'm
> > talking about convective heat flow, not radiative.
> >
> >    TIA,
> >    Chris C.
>
> Painting it black increases the radiant heat transfer.  Both ways, in or out.  If
> you paint it black and it's in close proximity of something hotter, like a header,
> then you'll gather heat.  If everything around it is cooler, than you will
> increase the overall heat transfer by increasing the radiated heat without
> changing the conducted or convected heat.
>
> Joe Boucher
> '70 RS/SS Camaro  '81 TBI Suburban