Leo Lichtman wrote:

CO2 is used in shielded arc wire-feed welding, so it ought to work in your
kiln. (And its cheap.)

But you also know, what really is happening with the CO2?
At welding temperatures:
If you have, say, SS, it will absorb C (CO2 - CO + O AND CO - C +
O). On the other hand, if you have a high carbon steel, it will loose
it's C!
There is a balance between the C-content of the gas, the C-content of
the wire and the C-content of the material. If you add C through the
wire, it has to be removed by the gas. And vice-versa.
You can observe this happening with Ar+18%CO2. And it surely will happen
with 100% CO2. You will add C to the steel (at 2000°C).
Also the O will catch some of the Cr (+Nb), if there is any in the
steel.


**But** I don't have the temperatures at hand, when CO2 dissoziates.


Nick
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