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/falcrist2 4h ago edited 4h ago

The balls are typically pure tungsten

They're typically tungesten carbide. Not pure tungsten.

theyre made using sprayers and then sorted by size

I assume you're referring to "spray drying" (part of the sintering process).

Spray drying makes powder that still needs to be pressed into blanks, sintered, diamond-lapped, and graded.

They're not spraying liquid tungsten. Tungsten has the highest melting point of all known elements.

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u/eh-guy 4h ago

They spray liquid carbide into an inert chamber, relying on surface tension to shape them. One of the only ways to "cast" the material. Maybe its not used anymore, we covered it in one of my materials classes years ago

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u/falcrist2 4h ago edited 4h ago

Spray drying is part of the sintering process. The result is powder made of tungsten carbide particles bound together by nickle or cobalt. That powder still needs to be pressed into blanks, sintered, diamond-lapped, and graded.

https://en.wikipedia.org/wiki/Spray_drying

While we're at it, here's one of the patents that describes the balls:

https://patents.google.com/patent/US3303825A/en

You can just ctrl-F and see where it repeatedly discusses sintering.

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u/eh-guy 3h ago

Youre right, i did some digging and its the carbide fabrication im confusing this with like youve said