So the prerequisites for this question are, of course, strength vs mass. The lighter, the better, in all circumstances, however it still needs to be strong enough to have people inside it and to hold atmosphere.
Aluminium seems like the default choice, but I was wondering if there were better alternatives. Aluminium would obviously be the -cheapest- solution, but I'm assuming money being no object for this.
Titanium was my next thought, but I'm not sure you gain a huge amount vs aluminium.
Then I started thinking about carbon fibre and kevlar-type products, but it's been very difficult to find information about the structural uses for carbon-based materials. It seems to be stronger, but also more brittle, and having things bend (aluminium) would seem to be better than having it shatter? Also carbon fibre seem to have issues with both heat and cold, neither of which is good for space it would seem?
Not sure if there are any other composite option out there. I've gone through the somewhat related threads on here but none seem to go along these lines, so thought I'd ask the question :)