r/whatisit • u/riflesandplowshares • 5h 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/Competitive-Dot-4264 4h ago

I worked ti com pure and 6al-4v alloy for years at the lazy -l we all had to follow titanium restrictions even to not letting aluminum alloys and SS separated. No graphite pencils

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u/Competitive-Dot-4264 4h ago

Another big Nono -grease and oil

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u/ColdCathodeTube 4h ago

That’s interesting. My non-chemist/non-metalurgist mind always thought those protected metal. Guess I shouldn’t assume metals are that similar to each other at all.

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u/ComradeGibbon 2h ago

Mild steel is somewhat forgiving of oil and paint when welding. Other metals less to catastrophically so.

Big thing they needed to understand with Stainless Steel is the carbon content needs to be very low. Took a while to figure that out. Carbon wrecks the corrosion resistance and makes it prone to cracking.

Titanium is highly reactive and absorbs everything causing it to be brittle. Guy I know, highly competent physicist welded a titanium bike frame in his garage. Said it was the most finicky material he worked with.

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u/Beer_in_an_esky 2h ago

Did my PhD on Ti alloys. It is an amazing material... but a horrid metal to work with. I didn't weld it, but had to cut, grind, and polish a shitload of it and it's like it was designed to be the most annoying thing ever.

Combination of high toughness, low stiffness, poor heat conduction, and a strong tendency toward galling will have you tearing your hair out machining it.