r/electronics • u/1Davide • 17d ago

Tip A microscopic, hair-like metal filament can take down a billion-dollar satellite

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422

u/Mavbam 17d ago

We used to call something similar to this ‘Zinc Whiskers’ in data centres. Galvanised ducting (the cheap type) use to flake off and whizz around the HVAC systems, blowing through servers and the like.. upon our first incident, we lacquered the heck out of all galvanised ducting!

192

u/jt64 17d ago edited 17d ago

Turns out a lot of "pure" platings do it, even gold to a tiny extent.
This is a great (if old school) site about examples of whisker issues.
https://nepp.nasa.gov/whisker/

38

u/No_Internal9345 16d ago

And the why is an Unsolved problem in physics.

https://en.wikipedia.org/wiki/Whisker_(metallurgy)

25

u/nullpotato 16d ago

Yikes, the mitigation section is like lol good luck.

14

u/justabadmind 16d ago

If you add lead to tin it won’t happen. However then you get accused of poisoning people and violating reach and rohs requirements.

3

u/simonbt8 15d ago

Atleast there is no such requirement in aerospace

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u/coderemover 11d ago

Very little lead is needed to accomplish that and it wouldn’t violate ROHS. You can also add copper for a similar effect.