World-First 'Super Alloy' Could Transform the Way Metals Are Made

https://www.sciencealert.com/world-first-super-alloy-could-transform-the-way-metals-are-made

by tejohnso • 13 days ago

101 59 13 days ago

anenefan2• 13 days ago

Interesting for products where the resulting alloy just needs machining - lathing, milling, drilling etc, but more interesting will be what processes will be needed to weld or form such alloyed metals.

bediger4000• 13 days ago

Existing high-strength alloys like MP35N are already extraordinarily difficult to machine. The "super alloy" in the story is said to have a compressive yield strength of 2 gigapascals, which is about MP35N tensile yield. Sounds like this "super alloy" isn't that much stronger than existing high strength alloys. It does have some fairly exotic alloying elements, tantalum, niobium and hafnium that probably don't come cheap. This super alloy will be used only in a very few applications.

anenefan2• 13 days ago

I have not struck MP35N afaik before, and interesting to see its use in commercial settings, and even available as bolts and nuts. Certainly not fun to machine [1]

It's hard to know just how much stronger this new processing of the alloy is than other common high strength alloys, as they list compressive yield and not tensile yield strength ... that's if the person writing didn't get the two terms confused.

As a note, I use duckduckgo and smirked somewhat at its search assist results for the few efforts to find the compressive yield of Bisalloy 400 (something I've had to drill) - checking out the listed sources it was clear it had mistakenly used the tensile yield ...

As an illustration for the differences, I found a page [2] for 4140 alloy and similar yield strengths. 4140 is reasonably workable, drilling isn't the greatest amount of effort either before it's tempered and annealed.

[1] https://www.practicalmachinist.com/forum/threads/milling-mp3...

[2] https://amesweb.info/Materials/Steel-Tensile-Yield-Strength-...

fwlr• 13 days ago

Presumably, some initial information was fed into the start of this reporting process. Multiple stages of this process had near-total incomprehension of the information yet performed full ingestion and reconstitution of it anyway, leading to this terminally-confused output.

smallerize• 9 days ago

I have to agree. It doesn't explain what a super alloy is or why this one is interesting. Fortunately it does link to the paper, https://doi.org/10.1126/science.aec4995 Also I'm not sure why Science Daily calls it the first, since there are others: https://en.wikipedia.org/wiki/Superalloy#Applications

rsfern3• 9 days ago

The science daily article is just incorrect to call this a superalloy, which it is not. This is a high entropy refractory alloy (HfNbTaTiZr), superalloys are usually based on lighter metals and they usually have only one dominant element while HEAs have 4+ dominant elements

Terr_• 9 days ago

PhD Comics: The science news cycle (2009)

https://phdcomics.com/comics/archive.php?comicid=1174

bitwize• 9 days ago

Now all we need to do is build an invincible giant robot out of it, to protect peace and justice from the forces of evil.

https://en.wikipedia.org/wiki/Mazinger_Z

https://en.wikipedia.org/wiki/Chogokin

The_Blade• 9 days ago

https://civilization.fandom.com/wiki/Giant_Death_Robot_(Civ6...

adrian_b2• 9 days ago

Unfortunately, the reality will be less spectacular.

Instead of one invincible giant robot, we will have invincible huge swarms of dwarf robots, which will be much more dangerous than any single entity.

rsfern3• 9 days ago

This is really cool metallurgy. They start with an alloy and deform it and because of elemental size mismatch they can cause the alloy to self assemble into nanoscale crystals with three different structures

The paper: https://www.science.org/doi/10.1126/science.aec4995

As an aside, “super alloy” is not the best wording choice on the part of the author of this sciencealert article, superalloys are an established alloy family that follow a different design strategy and have a very different composition profile https://en.wikipedia.org/wiki/Superalloy

hulahoof• 9 days ago

Buried in the article it sounds like the researchers consider it a Refractory High-Entropy Alloy (RHEAD)

mortarion• 9 days ago

This is basic metallurgy that every metal forger and alloy designer is already aware of.

rsfern3• 9 days ago

What aspect do you consider basic? I haven’t had a chance to read more than the abstract because of the paywall, but the really interesting thing here is the mechanically induced transformation that leads to a 3-phase nanocrystalline alloy. I haven’t understood the “fully coherent” part from just the abstract, but I think it’s a very novel report. It means they have three different crystal structures with seamless interfaces because all the atoms line up at where the crystals meet. To do that with three structures is remarkable. I’m not sure if it’s the first example, but I’m only aware of alloys with two coherent phases (some superalloys for example)

There’s some precedent for mechanical deformation to get nanocrystalline grain structure, and some precedent for mechanically induced phase transformations (see TrIP steels) but I consider both of those concepts pretty advanced

TrIP is probably the closest thing, but I’m not sure how widely known there are among the “metal forging” community? TrIP is usually targeting well known phase transformations to two-phase microstructures, here we have three nanostructured phases.

Finally high entropy alloys are absolutely not well understood, even if the idea of mixing a lot of elements and getting a disordered solution seems simple on its face.

TrIP: https://en.wikipedia.org/wiki/TRIP_steel

RobotToaster• 9 days ago

Anyone have an unpaywalled link?

marethyu• 9 days ago

So Gundarium alloy is getting closer to reality?

mcswell• 8 days ago

Right up there with unobtainium alloy.

prewett• 9 days ago

I guess I'm not impressed that some totally different alloy is stronger than steel. You can't change both method and alloy and claim that the method is better. Presumably the paper compared the same alloy using the normal and the new method, but this article omitted that essential information, and in so doing destroyed the result.

alwa• 9 days ago

I think that’s right, yes… from TFA:

It's two times stronger than steel, three times stronger than aluminum, and twice as strong as the same alloy made in a conventional way.

The source paper in Science, fwiw:

https://www.science.org/doi/10.1126/science.aec4995

And as a personal exercise in intellectual humility, I cast my eyes over the supplementary materials (as those are free-to-the-public)… I’d recommend it:

https://www.science.org/doi/suppl/10.1126/science.aec4995/su...

I get a huge thrill out of looking at serious work outside my expertise. When I’m tempted to imagine the proposition is as simple as it seems from the headline (or the article, or the editor’s note, or the abstract), it excites me to remember just how deeply and carefully and thoroughly people think through things I barely understand.

htlemur_bobby• 9 days ago

Hm I just read an article here recently that was saying that Americans had an edge in jet turbine blades production over china because Americans figured out how to make single crystal jet turbines using this same method. I wonder what the difference is.

SV_BubbleTime2• 9 days ago

So far as I know you could say Americans, but it is specifically Canada that most of the best engines are coming out of. Maybe Pratt and Whitney are using blades from USA, IDK, but anyone in jet aviation will be able to tell you the world would be fucked without Pratt.

ezst• 9 days ago

An edge that dates back to the late 60's/early 70's? How soft is that edge by now?

p_l• 9 days ago

The basics are pretty distributed, further work involved increasing lifespan at high temperatures, but also some work towards switching at least some turbine stages from separated blades into "blisks" - entire turbine stage is one crystal, including the hub.

lstodd2• 9 days ago

As hard as ever. US and USSR and EU has this tech, China, India and others still don't. When USSR tech was sold left and right in 1990s, China could not replicate it, although they surely got the documentation back then. Even now they can't build a reliable gas generator from 70s and are stuck at 1960s level with R-25 MiG-21-style engine replicas. They still try and fail to build AL-31 analogs (1978, Su-27 engine).

beambot• 9 days ago

The Veritasium video on how jet engine turbine blades are "grown" in an aligned crystalline structure for enhanced material properties (e.g. thermal performance) is absolutely fascinating & well worth a watch:

https://www.youtube.com/watch?v=QtxVdC7pBQM

zipy124• 9 days ago

This isn't exclusive to the Americans, do Rolls Royce in the UK not use similar methods?

iamflimflam1• 9 days ago

They do indeed - https://news.ycombinator.com/item?id=12474148

SV_BubbleTime2• 9 days ago

It's two times stronger than steel, three times stronger than aluminum, and twice as strong as the same alloy made in a conventional way.

Ugh. The most basic bitch metallurgy discussion possible.

Oh! It’s stronger than aluminum?! So is bronze, we’ve hard that for awhile! Is the new material lighter than aluminum while being stronger? Is it corrosion resistant? Is it machinable? Can you weld it? Does it oxidize? Does it lose all its strength under moderate heat? Does it temper, do you have to temper it? Is it inert? Can it extrude? Can it be formed into billet or just plate/bar? Does it shatter?

Oh but 2x stronger than <some steel> and 3x stronger than <some aluminum>… is that 2024 aluminum? 6061 common, 7075 aero? Is the steel cold roll or 600-series inconel?

This is an area where if you don’t know what you are talking about, STFU, because anything you say is just going to be embarrassing. This is a you don’t know what you don’t know topic.

As to “high entropy metals”, I’ve heard about this for awhile, I would expect it to be stupid low yield, stupid expensive, and hard to use. There is probably some grade-40 titanium ultra alloy that could make the same “strength” claims but no articles about it because it’s “cost prohibitive”.

… I count this as clickbait metallurgy. No thanks.

KingMob• 9 days ago

"How dare this Science paper summary designed for mass consumption, not meet my personal standards of metallurgical detail! Don't they know I read them?!"

adrian_b2• 9 days ago

Indeed, such "high-entropy" alloys have been known for decades, but they are rarely used because of high cost.

There is only one new fact in this research, which is however very interesting.

By mechanical working of the alloy, its crystal structure has changed to a mixture of grains with 3 different crystal structures, instead of being composed of homogeneous grains, like most solid-solution metallic alloys.

This change of crystal structure induced by mechanical working has doubled the strength of an already strong alloy, which is the novel and interesting result of this research.

The reason why this could happen is that the alloy contains similar amounts of metals that normally have distinct crystal structures. In alloys with a dominant metal, the alloy tends to have the same crystal structure as that metal, but in this alloy none of the crystal structures is preferred, so the grains take one of them randomly, during deep mechanical deformation.

perching_aix2• 9 days ago

I want to live in a world where these (important!) points are surfaced without their presenter sounding like they were personally insulted, and are frustrated to have to bring them up.

xxs• 8 days ago

alternatively, you ignore the feelings of all (hurt) parties and carry on. The original article is exceptionally poor when it comes to any detail.

I am no metallurgist, or machinist, or work in fabrication, at best I can qualify as a welder made by grinder and paint. Yet, reading that feels more like a sci-fi story (and even technologies that haven't been imagined yet) than just sci.

calibas• 9 days ago

This will be very useful if they can find a way to make it without something that costs $12,000 per kg.

A_D_E_P_T3• 9 days ago

Tests showed the new alloy achieved a compressive yield strength of more than two gigapascals while retaining its ductility, meaning it bends without breaking.

This is sleight-of-hand.

For metals, the operative properties are usually ultimate tensile strength and tensile yield strength. Compressive strength is typically a non-factor for most engineering alloys; only concrete is judged by its compressive strength, and sometimes various engineering ceramics. (e.g. SiC, compressive strength = 3.9 GPa.)

About ten years ago, there were a lot of papers on amorphous metal alloys that had "extreme strength" -- compressive strengths in the 5-6 GPa range -- but tensile strength was not reported and very low. Some measure of ductility was also present, but it too was very low. Those amorphous alloys were classical brittle materials; more ceramic-like than metal-like. I fear the same is probably the case here, with the alloy potentially fracturing along crystal type grain boundaries.

Until they report actual tensile strength and elongation, don't believe the hype. High compressive strengths are not very useful.

lnenad3• 9 days ago

High compressive strengths are not very useful.

I mean, it depends on the use case right? Modern tall buildings/skyscrapers with metal framing use metal pillars where high compressive strength is very useful.

A_D_E_P_T3• 9 days ago

Absolutely nobody is using an expensive novel alloy for 2GPa compressive strength. A 2GPa tensile strength, depending on various other factors such as corrosion resistance and thermal properties, could however be very interesting. (The strongest bulk steel alloys generally peak at ~3.6GPa tensile, which is approximately their theoretical maximum, but there are a lot of applications where steel simply can't be used. Nickel superalloys are typically 0.9 to 1.1GPa UTS.)

lazide4• 9 days ago

Interestingly, the design of beams and the like (used for columns) still means tensile strength is the limiting factor, not compressive strength.

For compressive strength alone to matter, you’d essentially need a solid steel column - which is so prohibitively heavy, it would often end up collapsing under it’s own weight (in tensile failure, most likely) before it got up to a useful height.

jordanb2• 9 days ago

Steel is used for compressive applications all the time, not only slender column.

iandanforth• 9 days ago

"Steel is one of the classic alloy examples: mostly iron with a dash of carbon and other elements, making it much stronger and harder than iron on its own."

Statements like this had me confused for years about how steel is made. Steel is raw iron ore with some carbon removed. (Among other things) Pure iron isn't common in nature, it's usually found instead with too much carbon. That is, to have the properties we like in steel.

jordanb2• 9 days ago

Main contaminate in iron ore is oxygen. The refining process is mostly removing stuff yes.

"Steel" is defined as carbon content between .02% and 2%. If the metal has less than that it's wrought iron. If it had more than that it's cast iron.

So steel is a range of carbon contents that gives particularly useful properties.

Historically the lower end of that was higher but with that addition of other alloys we have "low carbon steels" that behave like steel with very little carbon.

MeteorMarc• 9 days ago

Not only the initial strength is important but also the susceptiveness to crack growth during many years of stress. No idea how this structure would perform on this aspect.

ChoGGi• 8 days ago

I see they mention scaling up and time, something tells me this is cost prohibitive.

World-First 'Super Alloy' Could Transform the Way Metals Are Made

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