I can't think of any electronic component that will "burst" at
vacuum. After all, it is only 14.7 psi pressure change at most - even
if you pump down below a micron. You get down to 8 psi
I don't know of any specifically, but if Bob Bruninga, WB4APR, one of
the microsat developers (for US Naval Academy and APRS+AMSAT), is
concerned with testing for popping components as well as heat budget
when building cheap satellites from COTS components, it's probably a
real concern. Unlike vacuum tubes, our COTS components aren't designed
to avoid air inclusions in the package, and the adhesives don't have
to be high tensile in terrestrial use.
As the original question posed, capacitors would be specific concern
just thinking first principles, since the various manufacturing
processes have multiple ways to create air inclusions, and their
packaging is often such that the surface areas of the joints is far
less than the surface area of the plates, intentionally maximized.
Chip manufacture has intentional voids, but has strong bonding zones,
so I would guess more sporadic failure?
As I remember from trying to pump lasers system clean, water quickly
freezes if you try to vaporize a droplet in a vacuum. Then you have to
wait for it to sublime. We had lots of heating tapes on the chambers.
An IR lamp or heating tapes would probably help if trying to dry
something out, yes. AMSAT speaks of vacuum-baking.
As per Mt. Rainier, how long do you keep your personal electronics at
the summit? How quick does it trek up? Stratospheric service outside
the pressure cabin is higher and longer, I don't know if they have
issues. A Bell Jar will take it higher, quicker and for
freeze-drying, and hold it there longer. Likely the AMSAT folks are
just paranoid about a rare event, since it's worth checking all your
parts for rare failures because it's hard to replace a rare failure in
orbit, and it wastes so much effort & investment if one part fails
after launch instead of before -- but it doesn't hurt us to be
paranoid either, if the whole point is to rescue a phone.
The popcorn effect and the freeze-then-sublimate issues are TWO
reasons to do it at moderate partial pressure with a dry flow, not
hard vacuum. Did you try that with your gas lasers when trying to dry
them while evacuating?
--
Bill
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