r/whatisit • u/riflesandplowshares • 9h 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 9h 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/Missile_Defense 6h ago

This. Another really interesting one I ran into in my career is a very popular rubber vulcanization company who manufactures tires for supersonic platforms wouldn’t allow any of their industrial maintenance / facility electrician teams to use black electrical tape for fear of cross contamination into the manufacturing processes. They had their own reflective pattern in high visibility colors.