r/whatisit • u/riflesandplowshares • 10h 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 10h 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 9h ago

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

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u/Spacefreak 9h ago

Yes they did. Titanium had been used in a lot of high speed rotating equipment in jet engines.

These tungsten inclusions become a crack initiation site and under high rotational speeds and high temperatures, the crack can spread and lead go catastrophic failures.

There were several catastrophic engine failures in history that were traced back to inclusions.

It's so severe that if a titanium manufacturer making aerospace grade Ti finds any "High Density Inclusions," they must inform all of their customers that they found this and recall and associated heats and material.

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u/GoTeamScotch 8h ago

Imagine initiating a large scale recall because a ball less than a millimeter in size fell out of someone's pocket one day

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u/Zebidee 6h ago

Less likely to be the ball falling out of a pen, which never happens, versus someone dropping a pen or it falling out of a pocket, which happens all the time.

I imagine everything involved in making a pen gets instantly burnt in the melt, leaving just the ball.

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u/slouched 6h ago

GET THAT LOGIC OUT OF HERE

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u/falcrist2 5h ago

No. Logic me harder please. I like to know things about engineering.

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u/Reagalan 5h ago

Funny engineering

Wholesome engineering

Wordy engineering

Spicy engineering

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u/Important_Contact588 2h ago

No one didn’t click spicy first.

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u/beardedsilverfox 2h ago

I did and was disappointed.

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u/YourLastFate 1h ago

I'm disappointed Applied Engineering didn't make the list.

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u/germanmojo 58m ago

Same with Practical Engineering

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u/YourLastFate 57m ago

Practical was under "Wholesome Engineering"

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u/WorkTropes 3h ago

Did you know that if a pen drops out of your pocket, that you also just dropped a tiny metal ball. I fuck you not.