Todd Carrico wrote:

The fact that some ceramics have an extremely low conductivity (space
shuttle) does not mean that *all* ceramics share the same values.
Regardless of the thermal conductivity, the resistance to heat flow will
always be a function of the thickness.  My point was that without
significant thickness (let's say .03++) then the ceramics won't
substantially lower the pipe temp.  Cermamics that are applied this thick
tend to crack at high temp differentials and with big differences between
metal and ceramic CTE.  Witness the shuttle *tiles*, not shuttle ceramic
dip.  Ask the manufacturer why and how the coating is applied.  I expect

it

is inside and out, very thin, and done to prevent corrosion.

Jeff Spitzer

I beleive it is a powder coating process, followed by baking.

The reason I asked was to see if there was a cheaper alternative
to Inconel, that was as robust.

I am not sure I have heard anything here that would get me to try it.

No matter how cheap it is, if it doesn't work, and I have to go Inconel
anyway, I haven't saved myself anything but maybe furthered the cause.

tc

 
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