New methods can 3D print high-strength aluminum alloys


#1

Originally published at: https://boingboing.net/2017/10/25/new-methods-can-3d-print-high.html


#2

Aluminium is not an unweldable material.


#3

Cool? Definitely. But “faster and cheaper”? Only if you design parts unable to be made by traditional methods. As usual with 3-D printing, it looks brilliant for prototyping, but a non-starter for actual production of anything but absurdly expensive military equipment.

Does anyone know of a real mass produced product made with 3-D printing of any sort?


#4

Years ago I visited this company. They did 3D manufacturing of earpieces for hearing aids or high end in ear headphones. Say you want a better hearing aid fit. You get your ear laser scanned, the CAD is emailed to this company and printed in a 48" cube SLA machine with potentially 1000’s of other unique earpieces, all built in a single print in less than 24 hours.

Last I checked they still do plenty of prototyping side business, but its not their primary business.

http://www.intechrp.com/about-us/

I also expect medical devices to ease into this field as well - especially in orthopedics where everyone is a little different.


#5

Hearing aids. Fuel nozzles for jet engines.

But what does that mean in relation to this article? Additive manufacturing isn’t remotely a mature production process.


#6

Oopsie left out the word alloys. Fixed!


#7

3D printing equipment invisible to Allomancers? How perfidious.


#8

Not mass production.

Just that they always make these grand claims for it beyond prototyping and custom one offs. The fuel nozzle is interesting, but clearly just one step below military work in terms of an extremely high value part. My business is making custom things that I design myself for clients on traditional machine tools. In the decades I’ve done this I’ve only jobbed out work twice, to a water jet cutter and a 3d printer.

Good engineering usually involves designing within a practical and cost effective production envelope. Anyone can design something impossible to make except for 3d printing. Military production is an exception to all rules, which is why we get aircraft that cost as much as entire warship.


#9

Last I checked, Scadrial is still undergoing an industrial revolution period, so we shouldn’t have to worry about that for a few hundred more years.


#10

Exactly. The most problematic ones are high strength alloys of aluminum and copper (like 2024 alloy) or aluminum and zinc(7075 alloy). Even those are only unweldable using traditional methods like TIG welding. Both 2024 and 7075 can be succesfully welded by friction stir welding method. 6061 alloy mentioned in video is easily weldable, but joint has to be heat treated for full strength.


#11

Any meltable material can be welded, but it’s quite often economically impractical - for example it was far cheaper and easier for me to cast an aluminum porch post base and then machine down the casting that it would have been for me to weld one up - I melted the aluminum in an old coffee can.

And while welding even ordinary aluminum is difficult even with expensive equipment (TIG is the way to go, according to my welding consultant Pedro the Cruel) exotic aluminum alloys can be even more challenging!

You really have to know exactly what you are doing to weld aluminum properly.


#12

Well, that’s strictly true for any engineering activity. But welding (many) AL alloys is not any sort of magic; take a look at a modern motorcycle frame, or qute a few models of car. Hell, I’ve seen welded Al frame garden chairs on sale at Home Despot! With the proper welder and rod and gas it’s perfectly doable at home.


#13

I own a TIG welder and I can confirm this. While joints thicker parts came out ugly but ok, I also tried welding 1 mm aluminum sheets and it’s been a miserable failure :slight_smile:


#14

Have you tried it? With an expensive TIG welder it still looks pretty hard to me!

I watched a guy successfully weld a mercedes frame with a common nail connected to a couple of old car batteries. Granted, he was an EE - Do Not Try This At Home™.

But if you have the right mindset (the infamous “engineer’s mind?”) you can do all sorts of stuff without proper tools, knowledge or experience and still get away with it.


#15

If it was pure aluminum, didn’t you have problems with machining? In my experience it flows and sticks to the tool instead of forming proper chips.
I’ve always thought that casting is difficult, to the point that I just machine part from block, even if that means milling 80% of material into chips (like on the part below - frame for a small wheeled robot)


#16

I believe @AndreaJames is probably referring to something which is said about a minute into the video, which refers to aircraft aluminum alloys. While any base metal can be melted in principle, practically there are probably certain alloys the desirable properties of which would be negatively impacted by the heat required to weld them.


#17

On a side note…

As a mechanical engineer/materials geek, I LOVE Aluminum. it has just about everything you want. I’m an atheist but the fact that Aluminum is the 3rd most common element behind Oxygen and Silicon often makes me consider the existence of a higher power.

Forming? Its a dream to machine and low melting temperature makes casting inexpensive.
Lightweight? Relatively density but wait for it… Unrivaled specific strength aside from very esoteric shit (and Beta Titanium)
Still not light enough for you? It alloys nicely with Beryllium or Lithium or Magnesium…
Corrosion resistance? Damn good unless we’re talking about Mercury or Gallium
Visual appeal? Behold the beauty
Electrical Conductivity? Extremely good but copper beats it in this economy.
Thermal conductivity ? Basically only copper and Diamond are better. Most heat sinks are Aluminum
Sounds cool when British people say it? Check
Cost: Cheap enough to wrap chewing gum in it

“Now slow down, buddy… there are 13 protons in Aluminum’s nucleus!!!”

That’s why 13 is my lucky number.


#18

My fellow Americans are the only people I’ve ever heard drop the second i. Strictly speaking, aluminium is the original spelling, though I’m as guilty of mispronouncing it as anyone. :slightly_smiling_face:

It’s extra weird because I can’t think of any other metal element from which we’ve taken to dropping the i in -ium.


#19

Well, keep in mind I was “machining” using a table saw with a thrashed plywood blade. And it did clog up pretty bad - I took a picture!

I just kept picking the teeth clean periodically.

I did it without much forethought or experience, pretty much ignoring all proper technique… but keep in mind that probably the only thing easier to cast than aluminum is lead.

Oh, and if it isn’t obvious, easy is not the same thing as safe. Molten metal is dangerous and very unforgiving when it comes to personal safety… much like milling machines ;).

You can see where I had a couple steam explosions in one of those castings.

It’s definitely one of the issues. You generally want to heat-treat after you’re done forming the parts. But it’s usually an economic argument in the end, what’s the cheapest way to get to your end goal - often, with aluminum alloys, welding is not a cost-effective path. When I was in the aerospace industry we worked with a lot of aluminum and titanium alloys and almost never welded them, generally the process was cast -> machine -> heat treat -> test. 3D printing is going to add more cost/benefit options.


#20

What is the grand claim here? That a previously unweldable aluminum alloy is fusible at nanoscale? I see nothing about the impending 3D printer revolution. Further, the claim here seems like something only possible via additive manufacturing, why even fuss?

Production processes and the tools required of are in constant evolution, it is only your perception that is fixed. A blacksmith in 16th century merry olde England wouldn’t imagine the day that their hammer and anvil would become functionally obsolete, yet here we are, a blip in time further and Volkswagen produces mid-range iron horses almost entirely with robots.

A hammer and anvil could not suit the needs of the industrial revolution (Mao provided the proof) and burgeoning nations of millions. So too that time will come for subrtractive manufacture.

And it’s not some dystopian future planet with 20+ billion humans shitting all over it, I think, but our current reality which demonstrates the need to change our ways. To put it simply, I believe that we need to align human production with material reality, and additive/ molecular manufacturing- the ability to assemble things from their smallest parts, is a big part of that equation.

So right now, your machines are safe. All bets are off down the road tho.