components for a vacuum environment? 1

[schrand]

I'm searching for information about components that can and cannot be used in a vacuum environment. I already know to avoid paints, that solder will esentially evaporate (sublimate?) and that graphite becomes an abrasive, but can tool steels be used? silicone sealants? black oxide coating? Any information from personal experiance or web site tutorial / information pages would be greatly appreciated.
thanks,
david s.

 

[franck]

Hi Schrand,

I do not know where you got the information that paint, soldering or graphite cannot be used in vacuum/space. For instance, for soldering, as long as you have completely removed the solder flux, you should be fine. Silver soldering is allowed in a vacuum chamber. For some of the paints, as long as they have been properly baked it should be fine as.

The main requirement for a material to be vacuum approved is that its outgassing must be very low in order not to contaminate for instance optical instruments that can be within the chamber as well (or for space application). Finally I know plenty of graphite structures that went to space.

Please have a look at the following links to have a feel on what is accepted in vacuum:

http://outgassing.nasa.gov

http://www.ligo.caltech.edu/~coyne/AL/SYS/E960050-B.pdf

If you are interested about outgassing requirements, I can give you the one we are using in our company (should be the same than NASA and ESA)

Franck