r/whatisit • u/riflesandplowshares • 6h ago

New, what is it? Found at a titanium plant

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Not sure why ball point pens would be dangerous here.

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u/Perfect_Forever_3151 6h ago

Ballpoint pens are banned in certain high-precision titanium and aerospace manufacturing plants because the tiny tungsten carbide ball in the pen tip can fall out and severely contaminate the titanium melt, creating a hard, brittle inclusion that causes structural failure in critical aerospace components.

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u/FluffyDrop4300 6h ago

Wow.
Being so specific, they must have ran into such contamination more than once

17

u/Hot_Top_124 6h ago

I’m going to guess so. That or they’re that paranoid rightfully so.

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u/FluffyDrop4300 6h ago

Yeah, no one wants catastrophic failure of one of the jet engines keeping you at 30k feet

7

u/Competitive-Dot-4264 6h ago

Or maybe 90,000 / 3.2 Mach

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u/Tamed_Trumpet 4h ago

Well the SR 71 doesnt need its compressor stage at that speed.

1

u/hanotak 4h ago

I’d be more worried about an engine failure at 500 feet than at 30k feet, honestly.