We love our 3D printers. But sometimes we really wish we could print in metal. While metal printing is still out of reach for most of us, HRL Labs announced a powdered aluminum printing process that they claim is a breakthrough because it allows printing (and welding) of high-strength aluminum alloys that previously were unprintable and unweldable.
The key is treating the metal with special zirconium-based nanoparticles. The nanoparticles act as nucleation sites that allow the aluminum to form the correct microstructure. The full paper on the process appears in Nature.
Other than the nanoparticles, the process is a conventional laser sintered metal powder process. That’s not new. However, aluminum comes in alloys and not all the alloys are good for all purposes. Some of the alloys commonly used for high strength are not weldable and — in general — metal that won’t weld can’t laser sinter, either. HRL claims that 7075 and 6061 are both printable with this process. Presumably, other metals could benefit from this nanoparticle treatment, although different materials may need different kinds of nanoparticles.
We winced at the over-extrusion of the plastic part they show in the video, but hopefully, that was just a stock video. Of course, this isn’t going to make home metal printing affordable. Until that happens, you’ll have to settle for electroplating or you can print with lower-temperature metals.
How good are the lungs at clearing zirconium-based nanoparticles?
Nanoparticles cannot be assumed to be as benign as more macroscopic particles of the same material, due to their surface area/potential for enhanced reactivity and ability to penetrate tissues, so your question is a good one. Regulation of the potential hazards posed by nanomaterials is lagging in this regard.
How good are the lungs at clearing zirconium-based particles?
Meh,
https://www.cdc.gov/niosh/docs/81-123/pdfs/0677.pdf
Keep in mind the CDC is evidence based so they will pop up warnings after a significant number of deaths have occurred.
More of an issue is flammability.
https://cameochemicals.noaa.gov/chemical/8183
Moderation! Seriously?
How long is a piece of string, or more specifically how small a particle matters, of any type. The smaller a particle the deep it penetrates into the lung’s fractal structures, the finer the particle the more harm they can do and the longer it takes to eliminate them, if it is possible at all. See silicosis and black lung disease for examples, people die with it having never cleared out their lungs even after years of retirement and cleaner air.
How good are the hands in tolerating molten iron?
If you don’t get it: don’t breathe in the nano-particles and you don’t need to know, just as one shouldn’t pour molten iron on a body part.
Your analogy is well intentioned but wholly incorrect. In order to create molten iron, you generally need a furnace plus time and further, molten iron itself doesn’t really become airborne (though it of course gives off gasses). In contrast, you can fairly easily kick up literally billions if not literally trillions of atoms of nano particles with a small puff of air and because they are individually so small, they can linger in the air for a significant period of time as well as be considerably difficult to mechanically filter. Plus, it doesn’t evaporate so it never really just dissipates on its own either. It’s simply completely different.
Clearly one should not touch molten iron but the vectors of concern are completely different as to be not really something you can compare and contrast directly or simply hand wave away as not a concern.
“Until that happens, you’ll have to settle for electroplating or you can print with lower-temperature metals.”
Or print a mold and cast metal into that.
Or CNC what you want.
Additive processes can construct things that can’t be (CNC) milled so it isn’t a general solution.
I wonder how the process works with alumin[i]um powder and iron oxide powder?
B^)
It might be pretty thermally active. Plenty of videos of that out there. Could it be used to create anything useful though, maybe through selectively laying down different powders?
Thus the smiley…
Thus the suggestion that it “might” be pretty “therm”ally active.
I still maintain that it might be worth exploring the idea though of a very simple machine precisely laying down different powders and then starting a reaction in an appropriate environment to yield a useful output. Not sure how much merit the idea has at first glance but it could potentially be useful.
Throw in some TATP as an ignition source. All good!
This is awesome! The next advancement I’m looking forward to is selective powdering where you can use multiple materials. That ability would allow you to make pcbs into any shape you could think of which includes functional objects! :D
Recyclable?
Optomec has been doing this for almost a decade.
And you can use the left-over powder for binary explosives!