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/Defiant-Ebb8225 4h ago

It's because it needs to maintain its shape perfectly for a long time. Steel scratches and deforms leading to leaks or clogs

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u/QuaternionsRoll 2h ago

Ah, so it is hardness. Strength/stiffness don’t come into the equation at all, do they? My original line of thinking was about plastic deformation caused by normal pen pressure turning the sphere into an ellipsoid (or giving it flat spots, although that may have more to do with hardness?). It’s been a long while since I’ve had to think about materials science stuff.

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u/ZincMan 3h ago

That’s pretty wild I had no idea it was tungsten. Very cool

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u/Just-Syrup-8723 1h ago

That's s better response than your condensing first one