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Its got a whole heck of a lot more oxygen than any other atmosphere that I know of. 20% isn't bad.
I do know that if you are getting Ti red hot, you are absorbing oxygen into the metallic structure, and in the end, you will make your pot more brittle. Probably not a big enough problem to worry about with a pot though.


I'm not really planning on using my Ti pot in other atmospheres. <img src="/forums/images/graemlins/grin.gif" alt="" />

According to this link, Titanium doesn't burn in atmospheres with lower than 35% oxygen. Also, Ti alloys are fairly resistant to oxidation under about 1200F. Link

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Titanium has excellent resistance to gaseous oxygen and air at temperatures up to about 700°F (371°C). At 700°F it acquires a light straw color. Further heating to 800°F (426°C) in air may result in a heavy oxide layer because of increased diffusion of oxygen through the titanium lattice. Above 1200°F (649°C), titanium lacks oxidation resistance and will become brittle. Scale forms rapidly at 1700°F (927°C). Titanium resists atmospheric corrosion. Twenty year ambient temperature tests produced a maximum corrosion rate of 0.0010 mpy (2.54 x 10-5 mm/y) in a marine atmosphere and a similar rate in industrial and rural atmospheres.

Caution should be exercised in using titanium in high oxygen atmospheres. Under some conditions, it may ignite and burn. J.D. Jackson and Associates reported that ignition cannot be induced even at very high pressure when the oxygen content of the environment was less than 35%. However, once the reaction has started, it will propagate in atmospheres with much lower oxygen levels than are needed to start it. Steam as a diluent allowed the reaction to proceed at even lower O2 levels. When a fresh titanium surface is exposed to an oxygen atmosphere, it oxidizes rapidly and exothermically. Rate of oxidation depends on O2 pressure and concentration. When the rate is high enough so that heat is given off faster than it can be conducted away, the surface may begin to melt. The reaction becomes self-sustaining because, above the melting point, the oxides diffuse rapidly into the titanium interior, allowing highly reactive fresh molten titanium to react at the surface.