High pressure tungsten incandescent light bulbs?

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SUMMARY

High pressure tungsten incandescent light bulbs can theoretically achieve a melting point increase from 3422°C to 3700°C at 45 kBar. A 300 kBar bulb could operate at 5800 K with a luminous efficacy of 37%. However, the construction of such a bulb poses significant challenges, as it would require a steel casing instead of glass, which is impractical. Additionally, the extreme pressure raises concerns about the state of the gas inside, potentially leading to liquid formation that would enhance heat conduction and complicate design.

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James125
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With increased pressure tungsten has a higher melting point. (source below page 30) 45kBar increases melting point from 3422oC to 3700oC.

http://www.nist.gov/data/PDFfiles/jpcrd55.pdf

An ideal 5800 K black-body, truncated would be 37% efficient.

http://en.wikipedia.org/wiki/Luminous_efficacy#Examples

So extrapolating this graph a 300kBar light bulb would be at 5800k and 37% efficient. I know this an extremely high pressure but would this theoretically work?
 
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No, because you'd have to make the bulb out of steel, not glass. A steel light bulb won't work very well.
 
Pressure works out to be around 3000kg/mm2. I'm not sure if it's even possible to hold that in...Also I'm not sure if the gas inside would turn to liquid in which case it would certainly conduct the heat much more effectively, which would transfer to the case.
 

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