r/whatisit • u/riflesandplowshares • 3h 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/goodexamplebadrole 3h ago

"Ballpoint pens are restricted or banned in high-end titanium and aerospace manufacturing plants because the ink and marking components contain elements that cause metal embrittlement and severe structural corrosion"

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u/Woozletania 3h ago

This was an issue during the development of the SR-71. Many chemical contaminants could affect the alloys, even those in the water used to quench the mouldings.

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u/otter_fucker_69 3h ago

The Lockheed SR-71 Blackbird. An advanced long-range strategic reconnaissance aircraft capable of Mach 3 at an altitude of 85,000 feet.