Regarding the idea of a generation ship carrying a community of people for thousands of years to another planet:

Is there is any material for an engineered structure or set of systems that will resist oxidation for the many thousands of years required for the journey? 

Also, material fatigue and wear caused by the movement of people after just a few hundred years would soon compromise the structure. Almost all other items used daily will not last even one generation. The only way to overcome these problems would be to have a large number of spare de-oxygenated ships in tow to move into. 

I'm skeptical about the idea. I think the maintenance store would be too big. The whole thing would be too massive to get up to speed. Has anyone discussed this? Maybe I'm behind on it. It seems to be step 1 in engineering design for a reliable structure. Do we have the materials to withstand the conditions for the duration?