Hi all, this is my first post here, so I hope that someone finds it interesting. And also that there aren't too many grammatical errors. I like perusing scientific journals at work, finding articles that aren't too esoteric and then writing little summaries of them in plain language. If this sounds like something of interest to you, read on…
If you're not a regular reader of the journal "Science and Technology of Welding and Joining", you may have missed this notable little nugget. It turns out our Earth-based welding techniques don't work on space metal. Researchers at the Lawrence Livermore National Laboratory, in California, used a high-powered electron beam in an effort to weld sections of an iron-rich meteorite. Electron beam welding was chosen because it works in a vacuum - which is generally what you're dealing with beyond the Earth's atmosphere. While many Earth metals have been successfully welded this way in space, for repairs of man-made vessels and such, it turns out meteorite metals are a different beast altogether.
Upon cooling, the weld developed a number of cracks due to high levels of phosphorous in the material. On top of that, the high carbon content of the meteorite led to additional problems by increasing weld hardness (a thing that I have only just learned is not actually good) and the risk of cracking.
All this is important because if space colonies are ever to come to pass (and I like to believe they are, because cool), we probably won't be able to ships the necessary millions of tons of building materials from Earth. We've got to be able to work with what's out there. And so far, it turns out, we can't.
You can check out the original paper, 'Electron beam weldability of a group IAB iron meteorite', here.