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This is important, much more than most people think. You don't realize how many things around you need strong magnets.

> This technology for producing iron nitride permanent magnets has been exclusively licensed.

Interesting — I wonder to whom.

Agreed, I'm shocked I missed this when it was released in 2014. Rare earths no longer needed for magnets strong and light enough for windmills and electric motors? I remember the reports on how vulnerable our infrastructure was to neodymium supply disruptions, it was really high on the priority list. This is fantastic if it can be manufactured reasonably!
Windmills and electric motors don't actually require strong permanent magnets - electromagnetism/induction is somewhat more complex to manage but potentially more powerful and efficient. This is not theory or speculation - Tesla car motors don't involve strong permanent magnets [1] Large wind turbines do not require large rare earth magnets [2]

(Im not saying powerful magnets are not very valuable, but requirements for them can be overrated)

[1] https://forums.tesla.com/de_AT/forum/forums/no-rare-earth-me...

[2] https://www.mathworks.com/help/physmod/sps/powersys/ug/wind-...

Indeed, Hyperloop Transportation Technologies (the crowdsourced one) said they'd use Inductrack technology for their version of Hyperloop: https://en.wikipedia.org/wiki/Inductrack

This uses permanent magnets arranged in a Halbach Array for levitation.

This method of levitating a pod is incredibly efficient and gets more efficient at higher speeds (in a vacuum). You can actually exceed typical rail efficiency (rolling resistance of 1:1000, i.e. an effective coefficient of friction of 0.001 or a lift-to-drag ratio of 1000) at 300m/s since levitation power remains basically constant above a certain speed (as opposed to increasing linearly in the case of friction or rolling-resistance). And because you're in a vacuum, you're far exceeding what could be possible in a non-hyperloop/vactrain design: https://www.google.com/patents/US20100064929

I could come up with electrical motors and generators. Before that I saw them for controlling the arm of spinning hard drives, and those aren't used that much anymore. What else is there?
3M I guess
Fusion reactors?
"Theoretical limit of its magnetic properties are more than twice the maximum reported magnetic energy product for a rare earth magnet"

Call me a pessimist, but if the theoretical is more than twice the actual for rare earths that means the new magnet might well be weaker than the old ... in reality.

It's doubly suspicious that they don't mention the theoretical vs reality for the rare earths.

I don't think the theoretical maximum is wrong. It's just that the ion implantation can't be scaled up, doesn't work for bulk materials, and results in only ~40% of the material in the desired Iron Nitride form which has that theoretical limit.
The theoretical maximum for a neodymium magnet is grade N64, i.e. 64 Mega-Gauss Oersted.
But even if these magnets were only as powerful as rare earth magnets, the benefits to the environment are huge.
You're spot on. Compare theoretical with theoretical, actual with actual, damn it.
Thank christ, have you tried to source NdB magnets at quantity lately? I hope these get to be produced at scale soon, although unfortunately it sounds like the technology has been "exclusively licensed," which in my experience means a 500% markup from whatever its aiming to supplant once it finally hits production. The price of progress, I guess.

But yeah, I tried to order a few hundred rare earth magnets from China (where almost all of the world's rare earth metals come from) and got told that they can't export "pill-shaped" objects...bullshit, that's the same mealy-mouthed politically-backed excuse that they gave for not shipping a few dozen CCP badges through customs.

Anyways, the patent application doesn't make it sound THAT hard. Maybe it's something you could DIY for personal use: https://google.com/patents/US20140299810

Maybe someone who knows more about...all of this...can correct me, but tl;dr: Take an iron wire or sheet of diameter/thickness ~10μm-1mm. Strain it by pulling it in opposite directions, e.g. using two rollers pulling in opposite directions. While the iron is strained, heat it to ~125-600C in an atmosphere of N2 or N2+inert gas at ~0.15-1.5 Pascals for 2-10 hours. You actually need atomic Nitrogen and this part of the patent is vague, but I think ~500C might be enough to break the N2 bonds? They also describe a urea infusion process, but that sounds more difficult for a garage effort. Anyways, if that all works, it sounds like you can stack 'em to make larger and more powerful magnets. Anyone up for it?

There's a lot of canceled items in the patent, I wonder if that's because it was too vague to be part of the patent? I agree with your interpretation of the manufacturing process. They expose the sheet of <001> Fe to either nitrogen gas (N2) or NH3. NH3 does break apart with high temperature but ideally you want to work with N2 instead for safety reasons. It's more efficient to break the N2 bond using a cracking source, they use a plasma arc to break the bond of N2.

The usual problem is always going to be compositional control, you know, coming up with a method that preserves the rather excessive stoichiometry of Fe16N2. There's a bunch of other phases that can be achieved with simpler stoichiometries, so the long term stability of this magnetic phase is of concern to me. What are the ideal operating conditions of this magnet before interdiffusion occurs and we lose the right stoichiometry? Maybe there's a small window that could render this material inapplicable to many mechanical or thermal conditions.

Oxidation of the Fe sheet before nitridization is another concerns. Fe oxidizes very easily and would become a barrier for the nitrogen.

The other concern is that they characterize the magnet's performance only on the product of saturation magnetization and coercivity, and mention using ion bombardment to enhance the coercivity. This can be interpreted to mean that the Fe16N2 has a poor coercivity which means that it's a magnet that is very easy to switch with weak magnetic fields or thermal energy. Not what you want for permanent magnet applications.

So I still have a lot of questions and concerns although I do think it's worth pursuing this material because it makes a lot of financial sense as Fe and N are super common and easier to process.

http://www.designworldonline.com/coming-revolution-high-stre... (December 2014) seems to give a wider overview of non-rare earth magnet development: FeN, MnBi, Ce and exchange spring magnets.
Here is an article with a bit more info about Iron Nitride (it has quotes from Professor Jian-Ping Wang who is cited in the original link).

https://www.electronicsweekly.com/news/research-news/rare-ea...

Looks like there is a way to go before commercialization, but then that article was written in May 2016 so maybe they've improved the process since then.

> It is only a tiny sample, a film 500nm thick, but it is the real thing.

According to the patent application[0] it's from 2012.

[0]https://www.google.com/patents/US20140299810

Some important applications properties I didn't see listed in the brief UofM blurb:

Curie temperature: - at what temperature do these magnets start to lose their magnetic energy?

Coercivity: - how easily are these magnets demagnetized by external energy input (vibration, inductive kickback from motor windings, transformers, etc.)?

This looks to be up an update from several months ago, with graphs and data.

However the text is very domain specific, I can't follow it myself:

http://www.nanospin.umn.edu/new-magnetic-materials

They use the term "giant saturation magnetization" to describe an iron nitride magnet that they made. The saturation magnetization is the point where the magnetization in a material cannot increase any further. Think of it like a maximum strength of a magnet. Neodymium magnets have their saturation magnetization around 1 Tesla, and they reported that their iron nitride magnet has a saturation point at 2.68 Tesla, so it's greater. (The magnetics community likes putting words such as "giant", "colossal", and "extraordinary" in front of terms to emphasize how big something is. Especially when it comes to magnetoresistance)

BH max is a characteristic of a magnetic material. You can think of it as a kind of magnetic energy density rating, so more is better. What you linked to showed that the iron nitride magnet they made had a BH max similar to a neodymium magnet.

Also, I love the name "Minnealloy". Very Minnesotan.

I love how US beats foreign cartels or shortages by true technology (fracking, magnets).
This isn't just an American thing.
Interesting to note that this[0] article from Magnetics Magazine in 2016 has exactly zero mention of FeN magnets.

Vapor?

[0] http://www.magneticsmagazine.com/main/articles/permanent-mag...

Science beats scarce natural resources. Again
Call me when science transmogrifies base metals into gold for less than it costs to dig the stuff up from the ground: humanity has been trying since before science/ when science was alchemy.
This is interesting. I am an Electrical Power Engineer, and at my tech school, our Senior Thesis projects are essentially real Engineering firms coming to the school and assigning a group of engineers to work on a project they are actually working on in real life.

The company I worked under makes electric motors for navy ships and other government contracts. There are enormous machines in side of these things, but rare earth metals are economically volatile, on a scale unlike most other industries.

China and Malaysia have most of the rare earth metal mines (we had a bastanite mine in CA where you can mine for rare most of the rare earth metals, but the liberals did not want the pollution in California, so as a result, they closed down the mine (before it reopened for a bit and then went into Chapter 11 bankruptcy last year) and made America dependent on rare earth metals from Asia, where for a long time, and probably still now, they have zero emissions policies so we are effectively polluting the planet more (but not in my backyard so it feels good to feel clean and drive a prius as long as all the rare earth metals and pollution caused mining it are done by people working 1/26th the pay in China breathing in that air in not me, it makes me feel green), until Elon Musk has recently come and been working with mining companies in the U.S. for his operations.

At the time in 2011 when I was a senior working on this project and the explicit motivation for investing in research for this, China had overnight banned global trade on rare earth metals with 24hrs notice for 6months, to focus on their internal development, skyrocketing the price of 90% of the worlds rare earth metal production by over 9000%

At that time, my engineering group was contracted to come up do motor design and look for utilizing either less rare earth metals while meeting the same specifications for output or looking up for alternative metals.

We ended with a form of a Halbach array, which arranges rotor and stator magnets in a permutation of an orientation where the magnetic field is increased on one side and cancelled on the other, reducing the amount of loss not going into the relationship between the stator and the rotor and increasing the magnetic field where it did.

There is still a lot of need for this kind of design and optimization, and I ended up in a different niche of Electrical Power but, people were and are dishing out alot of money around this kind of work for good reason.

I looked up patents a few years after I graduated around this kind of thing and they have spiked up significantly in the passed few years, particularly with halbach arrays.

And you are right, most people don't realize rare earth metals are required in electric motors, wind turbines, inverters for solar panels and most movements we associate with sustainable energy, despite the fundamental components being extremely rare economically volatile, and relatively no innovation going on in the space of addressing these issues.

While the Mountain Pass mine had dumped a few hundred thousand gallons of radioactive liquid into the Mojave desert and did have pressure from environmentalists, it also got undercut by the Chinese.

It was restarted a few years ago in reaction to the possibility of the Chinese controlling a core of the defense supply chain, but again got undercut and the company that owns it is in bankruptcy.

And you are right, most people don't realize rare earth metals are required in electric motors, wind turbines, inverters for solar panels and most movements we associate with sustainable energy, despite the fundamental components being extremely rare economically volatile, and relatively no innovation going on in the space of addressing these issues.

Rare earth elements are required for none of those things. Some specific implementations of motors and generators use rare earth permanent magnets. Most wind turbines use doubly fed induction generators. Only a minority use permanent magnets. See e.g. https://pubs.usgs.gov/sir/2011/5036/sir2011-5036.pdf (a bit dated now, but best non-paywalled breakdown I could find with a few minutes' work)

Utility-scale wind turbines in use or under development in 2008 included double-fed, asynchronous (induction) wound-rotor generators (used in 73 percent of the wind turbines under contract for development in 2008); asynchronous generators with a cage rotor (14 percent); direct-drive, synchronous generators (11 percent); and permanent magnet generators (2 percent) to produce electrical energy suitable for transfer to the electrical power grid

I don't know about market share of RE PM motors in electric vehicles, but I do know that Tesla for example uses RE-free induction motors.

As for solar inverters, do you have a link to a diagram/documentation for an inverter that uses RE permanent magnets? I thought that I knew basically how inverters work, and I don't see where RE permanent magnets would even optionally go...

http://solar.smps.us/grid-tie-inverter-schematic.html

> but the liberals did not want the pollution in California, so as a result, they closed down the mine (before it reopened for a bit and then went into Chapter 11 bankruptcy last year)

Oh, so it was the fault of liberals, and not of dumping by China? That's news to me.

Besides, Tesla Motors has shown that the good old AC induction motor, which uses such rare materials as copper, iron, and aluminum, works quite nicely as an automotive drive motor. You seem to be conflating lithium mining with rare earths here.

First thought 'no way!' - neodymium magnets had a huge impact on electronics and mechanical systems... and then twice the strength? Incredible!
As another poster said, iron's theoretical max is twice the currently available rare earth strength. It's apples and oranges.
As a bonus - this is as environmentally friendly and cheap as they come.

We have a lot of both fe an ni.

> We have a lot of both fe an ni.

Nitpick - "Ni" stands for Nickel. The magnets described in the article are Iron Nitride - that means Iron and Nitrogen (Fe16N2), not Iron and Nickel.

Your point stands - Nitrogen is extremely abundant.

It's a miracle. How do they work?
Can we get a [2012] on the title?
Title has apparently been changed to 2014.

Has anything come of this revolutionary creation since? I.e., any actual magnets in production?

Goes to show that stupidity isn't dead. I wonder what kind of "licensing fees" will they require? I also wonder how much of this research was paid for by public money?

Instead of making this available to everyone so that these kinds of magnets can get out there, they want to scrooge first. If I recall correctly, universities that have gone down this path have simply stalled the progress of mankind instead of pushing it forward.

The University of Minnesota licensed Gopher in the early '90s. Until Gopher had its lunch eaten by a public domain WWW.
Damn right. And just one sentence above they go on about the environmental harm rare earth extraction causes. Surely if this was a real concern just 'licence' the tech for free. I would expect universities of all organisation to understand that baking a bigger cake means more cake for everyone. Fighting like jackals over scraps is what I expect 'business' to do. But uni's have become big, inefficient fascist diploma factories, and you can tell.
If public money went into development - the public is definitely entitled to a cut.
You can bitch about it when we will all have basic income until then they are doing what any other inventors are doing.