What materials would be useful in constructing a Space Station?

Question

For the obvious reason of weight, our modern space stations and satellites are made out of metal or lightweight compounds to reduce cost. In a quick Google search, about $20,000 per kg is the cost, to be exact. This limitation greatly influences the actual construction of stations. But what if the material cost was roughly the same as it would be for building a structure on Earth itself? It's the future, we have a Space Elevator, space asteroid mining, in-situ manufacturing, you name it we have it. How would that change our station designs? Would several feet of concrete or solid sheets of lead be useful for blocking radiation, etc.? What about other materials we commonly use, like wood, or clay?

The focus here is on creating a 'good enough' station with already existing materials (2018), and examining the uses of said materials in space. Other considerations are secondary. As some pointed out, more advanced and useful materials exist, but are not being considered due to the large increase in price. They are utilized in more important works, such as military stations and the like, but for your run of the mill habitation station, it is excessive.

For the purposes of the exercise, the following holds:

• The cost of materials is the same as what it would cost on Earth, plus some % that it took to take it into space. So cheaper materials will always be cheaper than more expensive ones.

• The 'economy' of supply and demand is considered to be the same as well, for simplicity's sake, so metals will not end up being the dominant force in terms of cost due to asteroid mining.

Answer 1

For all the major stuff, since you have a space elevator you don't need to worry about weight, just usefulness and cost. Here are my thoughts:

• Lead for the exterior shell and exterior window shutters. It's cheap, durable, corrosion resistant, and it's a good insulator of radiation.
• Steel alloys for the interior walls and essential (deck dividing) doors. We've got some good durable cheap steel alloys in the works these days. (it's a link!)
• You don't need much more than cheap plastics for nonessential (non-safety related) doors an
• Advanced durable ceramics (another link!), lined with electrochromatic glass, for any windows.

For hermetically sealing the craft:

• You could run treated concrete between the lead exterior and steel interior to ensure no gaps, but if this space station is going to be very big or if it's going to have any components which vibrate a lot (like some kind of spinning futuristic motor that vibrates for some reason), then you're going to want to run with a plastic-reinforced concrete, or none at all. Concrete cracks over time, and it's not easy to repair without removing and replacing it.
• Rubber is a good choice to seal the ship. It's cheap and it lasts a long time. Getting the right kind of rubber might be somewhat expensive, but the materials themselves are probably going to be much less costly than the tests to ensure that they were installed correctly.
• If you want to be original, you could use wood sealed with tar and pitch. It's not very size/weight-efficient, but it's very effective for hermetically sealing a thing, and it's flexible and durable so you can put put a layer of wood between your lead exterior and steel interior, and grout the gaps with tar. The price of wood varies quite a bit, though, so getting the best kind of wood might be more money than it's worth.

I hope this helps!