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4

“Sheets of stacked graphene”? Ok: look no further than graphite, AKA carbon. It very much is used for its thermal properties, in applications such as electrodes that can withstand molten aluminium. And, indeed, heat shields. Specifically, carbon fibre reinforced carbon, which is what the Space Shuttle's leading edges were made of. Now, ok, graphite isn't ...


3

Disclaimers: This answer provides some more details about the engineering problem of trying to reuse an ablative heatshield. This discussion/analysis could arguably by better suited for the question What are the major challenges faced in designing a reusable heat shield? but I think the wording of that question and existing answers precludes ablative ...


30

For a non ablative heat shield you need a material with a very high melting point and a very low thermal conductivity. It should not burn in hot air. Unfortunately graphene seems to have a high thermal conductivity, higher than pyrolytic graphite. In-plane thermal conductivity could help to avoid hot spots, but through-planes conductivity should be low as ...


22

“Aluminum, rather than steel, comprises most of the outer shell of the modules” https://science.nasa.gov/science-news/science-at-nasa/2001/ast14mar_1 . Aluminum has low melting point and softens significantly before it melts. Aluminum and Titanium are major components of the modules. Both are combustible. Titanium will burn in nitrogen, in the absence of ...


11

This (not so new) article says it can: "NASA estimates that 16 percent of the ISS would likely survive the burn and stresses of reentry, between 53,500 and 173,250 pounds falling to earth. "


5

In lieu of authoritative data there is always homebrew simulation. The necessary details about Crew Dragon & its entry, short of aerodynamics, are relatively easy to find: Parameter Value Justification Final Orbit 418 km x 22 km curve fit of altitude callouts from Demo-2 splashdown livestream Cross-Sectional Area 12.6 $m^2$ 4 m diameter circular cross-...


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