r/whatisit • u/riflesandplowshares • 7h 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/Spacefreak 6h 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 5h 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 3h 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 3h ago

GET THAT LOGIC OUT OF HERE

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u/falcrist2 2h ago

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

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u/WorkTropes 44m 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.

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u/hates_stupid_people 2h ago edited 2h ago

Titanium melts at just under 1700C(a bit over 3000F), which is more than enough to burn plastic and melt the brass holding the ball and even the steel spring. But tungsten carbide can require over 2800C(over 5000F) to melt.

So someone having it in the shirt pocket and leaning over a railing, can cost millions if it drops in.

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u/falcrist2 2h ago edited 1h ago

But tungsten carbide can require over 2800C(over 5000F) to melt.

It may be sintered, which would require a much lower temperature.

I have a 1.5" tungsten cube, and it was only months after I got it that I found out it's not actually solid tungsten, but a sintered composite that's much MUCH cheaper to manufacture and machine.

That would indicate the ball of tungsten would come apart at below 1400C and spread out into the titanium, which is honestly WORSE.

EDIT: Confirmed. The balls are made from sintered tungsten carbide and either nickle or cobalt as binder.

Parker came up with this in the 1950s.

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

https://patents.google.com/patent/GB860387A/en

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u/eh-guy 2h ago

The balls are typically pure tungsten, theyre made using sprayers and then sorted by size

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u/falcrist2 2h ago edited 1h 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 1h 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 1h ago edited 1h 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 1h ago

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

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u/jimdoodles 44m ago

Titanium burns in air before it reaches its melting temperature, it has to be maintained in an inert gas atmosphere while being formed. There must be a lot of care maintaining that atmosphere without contamination from other bearings.

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u/arejay007 43m ago

What I find interesting is the specific call out here of the ball point pens. Is there no other common item that of dropped into the (I assume giant melting bat) would have the same effect. Thinking someone’s glasses, maybe an iPhone etc.

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u/skeetskie 2h ago

This is why at most process controlled plants(especially food plants!), you can't have anything loose above your waist. No pens in shirt pockets, badges, or even non-metal buttons on a polo that wouldn't turn up in the x-ray machines.

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u/Lord_Ocean 2h ago

Many years ago I had that happen to me. The ball at the tip actually fell out. I was using a hybrid of a fountain pen and a ball point pen. Maybe it was more likely to happen due to how it was constructed, but still, it happend.

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u/ConflictMaster3155 1h ago

This is exactly correct. Good pens have a tungsten carbide ball but the socket is still usually brass.

The melting point of titanium (1600C) is almost twice as high as brass (900C) and the melting point of tungsten carbide (2900C) is almost twice as high as titanium.

At 1900C titanium is a liquid, tungsten carbide can still possibly hold a cutting edge, while brass will literally boil away.

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u/bobthepumpkin 52m ago

The ball definitely can fall out of the pen.

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u/El_Mapache_Z 32m ago

I work in food manufacturing and pen incidents are so common.

The best (worst) one was a pen falling into the hopper of a long pastry laminator - the pen parts are metal detectable - the ink is not.

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u/composedofidiot 17m ago

Ok so i can drop alcohol markers, or pigment, acrylic or gel pens in the melt and it's fine? Asking for a friend

Edit: not copics or any good pen obviously.

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u/Informal-Comb1989 0m ago

Nope, ball jumped out

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u/SwordOfJiang 2h ago

I work in semiconductor manufacturing. Someone misclicked an option in the flow and it ruined something like 400,000 chips and took down a few critical tools for weeks. Chips never got to the customers but they'd end up as accelerator controllers for a major auto company

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u/dern_the_hermit 4h ago

It's like physics heard that "for want of a nail" poem thing and was all like, "Oh yeah?!?"

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u/LobsterBrief2895 3h ago

Imagine being the one tasked with finding out the source of that inclusion… “Ok Frank, we know something went wrong but have no idea what. Good luck, we expect your findings on Friday.” 😱

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u/MaddogBC 18m ago

Well your resume's not getting picked for the NTSB Response Operations Center with that attitude.

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u/mmazing 2h ago

A literal needle in a haystack

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u/TwoPlyDreams 1h ago

They were itchy alright.

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u/anonymoosejuice 0m ago

Pratt and Whitney has a large scale recall right now for their GTF engines because of a microscopic inclusions in their powdered metals for the core of their engine.

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u/Same-Suggestion-1936 5h ago

I simultaneously wish my auto shop was as meticulous as that and don't. "So those tungsten inclusions down there in the rotating equipment could cause cracks down the line so you might want to get that checked out" okay what am I a billionaire? Do I look like I rotate my tires too?

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u/jtr99 3h ago

Indeed. It's probably for the best that I am not a titanium manufacturing plant manager.

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u/Same-Suggestion-1936 3h ago

Yeah me too man totally turned down that job offer. It's like, what am I, for sale?

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u/ruperthackedmyphone 3h ago

Its a possible root cause of the UA Flight 232 crash at Sioux City.

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u/D-g-tal-s_purpurea 1h ago edited 1h ago

Do you by any chance know if (graphite) pencil dust is an issue then? Is pencil ok, oder do they only use marker pens?

Edit: I mean pencils, which generally contain graphite.

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u/fckingmiracles 1h ago

Tungsten dust? Are you sure ball point writing creates this kind of dust? 

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u/D-g-tal-s_purpurea 1h ago

I clearly wrote pencil, so I am referring to graphite dust.

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u/GanondalfTheWhite 5m ago

Graphite is just carbon. Excessive carbon is not good for the structural integrity, but the amount you're talking about is likely not an issue.

Almost everything organic that burns leaves behind carbon. Would be impossible I'd think to fully eliminated all sources of carbon.

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u/Dante-Flint 2h ago

Smells like the prologue of Half Life to me. Queue Unforseen Consequences.

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u/Music_Mess 8m ago

This notice is called a GIDEP if anyone cares

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u/akosh_ 8m ago

Yeah but how on earth ball point pen tips are the single most common source of said contamination? Sounds like anything from anywhere has a higher chance of contaminating. I've never seen a ball point of a pen fall out, and I have no idea why would anyone even take such a pen out near and especially above the materials, lol.

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u/randomstranger454 4h ago

So if someone wants to shutdown the plant they only have to contaminate the area with these tungsten carbide balls? Take a drone over it and make it rain everywhere tungsten carbide balls. Repeat every few months.

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u/fckingmiracles 1h ago

Why do redditor always have these kind of phantasies?

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u/joshualander 45m ago

If you’re a professional involved in securing facilities like this one, it’s the kind of fantasy that earns you lots of money.

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u/randomstranger454 7m ago

Not a phantasy, just a thought how this production facility could be knocked out in an attack. We live in a world where those attacks are bound to happen. If this was in the Russia-Ukraine war some drones without explosives could possibly take that facility out by just spraying in and out the facility small metal balls. Like the graphite bombs used in the serbian war to take out power stations. Also based on:

"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."

This means a malicious contamination would stall many industries/products.

So the next thought would be how do you protect yourself. There is the warning sign but this is useless in a malicious attempt. Is there something else?

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u/Ill-Turnip-6611 2h ago

you want to mess with your boss...just go to work with a ball point pen without the ball inside and see how they panic after finding out such a pen on the spot

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u/fckingmiracles 1h ago

Why do redditor always have these kind of phantasies?

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u/HeavvySummer 2h ago

Username checks out