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View Full Version : Space Welding- Fact?


moldybread
03-11-2010, 10:04 AM
In space, touching two uncoated pieces of metal will instantly fuse them together. The Earth’s atmosphere coats metallic surfaces with a layer of oxidized material, but in the vacuum of space, no such layer exists.


Is this a true statement? Sounds a bit off to me. Can someone please expand on the actual process?

Machine Elf
03-11-2010, 10:08 AM
It won't be a very strong weld, since theoretically you only have three points of contact - unless you're able to machine your two pieces really, really flat. Like gauge-block flat. (http://en.wikipedia.org/wiki/Gauge_block)

Squink
03-11-2010, 10:43 AM
Employing my vast power of google-foo, I found this at Wikipedia:
Cold Welding (http://en.wikipedia.org/wiki/Cold_welding)

Mechanical problems in early satellites were sometimes attributed to cold welding. However, in 2006, Henry Spencer stated that the phenomenon of spontaneous cold welding in outer space is "basically a myth", pointing out that "there are no documented cases of it actually occurring in orbit, except in experiments deliberately designed to provoke it (with susceptible materials, great care to avoid contamination, and deliberate mechanical removal of oxide layers, etc.)."[1]
The ref is to this google groups post (http://groups.google.com/group/sci.space.history/msg/9f09b7136c1206f5), so it may as well be written in stone. ;)

moldybread
03-11-2010, 11:01 AM
Ahh so my suspicions were correct. Thanks!

eldowan
03-11-2010, 12:16 PM
Here is a link to an article about cold welding here on earth, with silver and gold.
Though it isn't what the OP was asking about, I thought it was a neat read.

http://www.physorg.com/news185467550.html

moldybread
03-11-2010, 12:21 PM
Pulling the wire apart gave the team a measurement of its strength. What they didn't expect to see was the broken wire mending itself when its ends or sides touched. Measurements showed the reconnected wire was as strong as before.

Pretty neat! Thanks for the link!

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