Most of our ultra-high strength alloys, and the theoretical ones that go above them, are entirely dependent on their molecular geometry for their strength. [a macroscopic object composed of fullerenes, pick your elemental variety, any, they are all mindbogglingly, stupidly, strongMany alloys simply cannot be made in any sort of continuous acceleration, because of hugely differing properties, and so you just don't have them here on earth. Those same alloys though are some of the strongest ones we know of. It's also much easier to make a nanoscopic structure, when you don't have to worry about bits and pieces of it breaking off under their own strain before the final structure can be realized.So yeah, research stations in space would be good for materials science research.The thing that irritates me the most is - why the hell are we building crap on planets in the first place?Resources in space are HUGELY more accessible than they are on a planet, and thar be more space to boot.Just to give you an idea of the disparity between resources in space and on earth - your average icy body of only a few dozen miles in diameter contains several HUNDRED THOUSAND times the total amount of potable water on the planet.Your average metallic roid of only ten miles in diameter would supply enough iron/steel for the whole of human history's endeavors with metalworking, and the next 10 years of metal consumption at our current rate. That's one pretty small roid. Just send off a single Von Neumann machine, come back a month later, and you've got a mountain's worth of metal to turn into whatever shape you desire.It might be worth mentioning that it'd actually be a pretty bad idea to make a space ship entirely out of metal - most metals actually become x-ray radiation sources because of Bremsstrahlung radiation - where high energy particles above a certain point cause radiation to be produced from the very action of decelerating them by another charged particle [high energy electron smacking a nucleus] and then you get x-rays to the face.Not a good idea if your 5 feet away from a star's corona.
your thinking to much about facts

give your fantasy a lil room... ship cost metal..... who said it's iron??? or any other known alloy?
ships cost credits.... doesnt that include the purchase of "manmade" materials?
ships cost crystal.... (as far as i know crystals are worth alot) you cac use em as superconductors ... sell em... trade em.... redesign its amic structure
anything is posible.. dont draw conslusions about what is real or not.... cuase fantasy is here 2 fill up the gaps (tough im still unsure of why icy planets are found closeby the sun and vulcano's in the outer SS)