Originally published at: https://boingboing.net/2018/07/25/this-3d-printed-titanium-fuel.html
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So how do they do it usually? Carve it out of a block of titanium?
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Man, just look at all that titanium…I mean, I dunno what I’d do with armour made from titanium, but that doesn’t stop me from wanting some.
I wonder what was the previous process like, so it would take so much time.
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I know Titanium is not an easy metal to work with, but taking 2 years to build a single part seems excessive. I assume that a big chunk of the time is taken by running an X-ray microscope over the entire thing looking for imperfections in the material, but that should be the same for either process. I imagine the 3D printed version was printed in a couple of weeks and then certified over the next 2.5 months. The traditional one would be fabricated in 21.5 months and then certified.
Maybe the old system needed an absurdly slow cooldown process for proper crystallization? Like literally months cooling from working temp to room temp. Multiple times. Not like there is a full time employee hammering the thing by hand every day for two years.
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slowly… slowly catching up to SpaceX, who has been 3d-printing their engine nozzles for years now:
The SuperDraco engines on the crew-rated dragon (used for crew escape) are 3d-printed as well.
Pretty awesome to see such critical components printed!
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My thought exactly! Also, this quote from the linked article:
Traditional manufacturing techniques also meant that more than 80 percent of the material went to waste.
So is there some metallurgical reason that titanium scraps can’t be melted back down and used for other parts?
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go to Baikonur and pick some up the next time there’s a launch. Scavenging rights are open.
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Some of the specs I read said that the bulk of the time spent in manufacturing involved precision milling of the die. I don’t know if they were stamped of forged, but in either case, it’s a long process to make a die with required tolerances. Those domes are probably not standardized, so it’s a new die each time.
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The company that would do that is not the same one that’s machining the metal. Also, titanium is not scarce, the expense comes from getting it into a usable form.
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Damn, there’s no pictures. But this article mentions a Captain America looking shield made from titanium: http://www.kcloves.com/home/stories/hammerspace/
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Fabrication certs (dye-penetrant and radiographic inspections) shouldn’t take that long. The article mentioned “final rounds of certification testing”. “Final rounds”. Because it’s a new process, I wonder if testing took place with the still-in-progress dome removed each time (iterative process) for the dye-pen and X-ray. Found Issues could feed into needed adjustments at the 3D fabricator? Just guessing… time for some research!
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Perhaps forging?
The “waste” was most certainly collected and sold for recycling but at a fraction of the original material’s cost. And I don’t know how well titanium recycles compared to something like aluminum (where 75% of all the aluminum ever produced is still being used).
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I’m guessing it’s a similar situation to Aluminum where you can use the leftovers, but generally only for less critical applications. It’s been ruined for airframe use, but you can still make beer cans out of it. This is a common problem with alloys.
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Did you mean the Draco RCS engine nozzles or something?
SpaceX’s Merlin engine nozzles are not 3-D printed. They’re a channel-wall design featuring a mandrel-forged copper inner liner with machined regen channels, capped by a stainless-steel outer skin that is (explosively, IIRC) welded to the copper liner.
The SuperDracos, as you say, are entirely 3-D printed of Inconel, including the containment ‘bathtub’ that protects the capsule interior from a catastrophic engine failure.
Rocketlab, which recently launched the first successful test flight of their privately-funded Electron smallsat launcher, uses their Rutherford engine in a 9-engine cluster on the first stage, with a single vacuum-adapted copy on the second stage, sort of like a miniature Falcon 9.
Rocketlab 3-D-prints the entire Rutherford engine in three major pieces. It’s a regen-cooled engine with unique electrically-driven propellant pumps, which greatly simplify the plumbing.
Rocketlab can build an entire motor in one day.
Also, keep an eye on Relativity Space, a new smallsat-launcher startup that plans to 3-D print their entire rocket - engines, tanks, payload shrouds, the whole works – and they’ve already built the printers they need to do that.
And of course even Old-space contractors are starting to adopt 3-D printing: Aerojet Rocketedyne recently completed tests of a 3-D printed chamber and nozzle for their venerable RL-10 hydrolox upper stage engine, replacing the expensively hand-crafted tube-wall chamber that’s been used on the RL-10 since its debut in 1962 (!).
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Ti must be forged in an oxygen free environment (ex: pure argon). Titanium is a bit of a pain to work with because it reacts chemically with a lot of things when hot, and it gets too hot easily. Even grinding it and welding it can cause it to react to the air or with oils transfered from your hands. Oxygen, Chlorine, and Aluminum are all bad news for Titanium. (popular alloys are with aluminum, but something like aluminum oxide reacts and forms brittle material)
The 3D printer looks like it is laying down a weld in a circle, and that entire spindle is almost certainly in an argon atmosphere.
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You can turn it back into Titanium sponge using a chemical process. In the steps of making the spong the other metals in your alloy will form different compounds you can easily remove. Costs will be similar to processing raw ore, so I think it’s cheaper to sell alloy scraps to be used for making lower grade alloys.
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Impressive.
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Now I want to see video of that process.
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