High pressure tungsten incandescent light bulbs?

AI Thread Summary
Increased pressure significantly raises the melting point of tungsten, with 45kBar elevating it from 3422°C to 3700°C. A theoretical 300kBar tungsten incandescent bulb could achieve a temperature of 5800K with 37% efficiency, but practical implementation is problematic. The bulb would need to be made of steel instead of glass to withstand the extreme pressure, which presents its own challenges. Additionally, there are concerns about the gas inside potentially becoming liquid, which would enhance heat conduction and complicate the design. Overall, while the concept is intriguing, significant technical barriers make it unfeasible.
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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