The main heater coil will be completely encased in alumina to keep away the air (O2). It looks like we will insert the inner coil inside the alumina heater tube and then will use alumina cement to close off the ends from air, so the only air that it is exposed to is that which is in the volume trapped inside - not a continuous fresh supply. Alan has tested this coil in free air as well, but not to destruction.
We hope to get solid tests at 1200C and after all of the data is captured, try to increase to 1400C taking data along the way, knowing it could burn out at any moment. All we need is one good test set. If we have to, we can always build another. On Mon, Dec 8, 2014 at 11:11 AM, Bob Cook <[email protected]> wrote: > Bob-- > > The MFMP test as you describe seems to me to be well thought out, and your > evaluation of the Lugano test probably correct. I also think Jones is > jumping to conclusions. We will see with the results of the MFMP testing. > I hope your estimates about the lifetime of the electrical wires at 1400 > degrees C is borne out. That's pretty hot for any metallic wire subject to > oxidation in my experience. > > As an additional design feature, you may want to keep the oxygen low with > a nitrogen or inert gas blanket to extend the wire lifetime. > > Bob Cook >
