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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 nit
by jwr 9y ago
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.
- VMG 9y agoI 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?
- falsedan 9y ago> spinning hard drives, and those aren't used that much anymore Hey! Are you basing this statement on your own experience of your personal/business hardware? Because spinning rust has never been more heavily used, for bulk on/near-line storage. Judging by the list of alumni from Prof. Wang's group, HDD manufacturers have a strong demand for advanced applications of magnets, plus a tiny fraction from biomedical techs. [0]: http://www.nanospin.umn.edu/people-0 http://www.nanospin.umn.edu/people-0
- VMG 9y agoYou were right, I did not consider bulk storage outside my personal use. Thanks.
- theandrewbailey 9y agoHard drives are one of those big technologies that are more widely used and more important after they are obsolete[0]. [0] for some definition of obsolete.
- lloydjatkinson 9y ago> spinning hard drives, and those aren't used that much anymore. Not sure if serious or not. Just because SSD's are popular, does not mean HDD's are unused.
- CamperBob2 9y agoLow-field MRI could probably benefit from a 2x improvement in the state of the art.
- lostlogin 9y agoHigh temperature superconductors are what MRI needs.
- CamperBob2 9y ago"MRI" covers a very wide variety of imaging and analysis techniques under the general category NMR (Nuclear Magnetic Resonance). Some forms of NMR analysis actually use the Earth's magnetic field (https://en.wikipedia.org/wiki/Earth%27s_field_NMR https://en.wikipedia.org/wiki/Earth%27s_field_NMR). Basically, the stronger the fixed magnetic field, the more you can see and do.
- lostlogin 9y agoExactly. Super conductors are the ones I use and high temperature superconduction will likely make maintaining a super conductor much cheaper (after you spent lots on a whole new system).
- comboy 9y agoWhy is this being downvoted? Prev post said you don't realize how many magnets are around you, so the parent is asking. I wanna know too. I additionally came up with speakers/headphones, connectors, reed switches.
- pingec 9y agoHere are some more items I can think of: speakers, earphones, magnetic switches (eg. laptops), relays, sensors, CD/DVD ROM, maglev.
- beaconstudios 9y agoAFAIK they all use electromagnets rather than permanent magnets.
- AlexandrB 9y agoLast time I checked speakers and headphones still had a single permanent magnet + an electromagnet. However, for speakers, the "old" iron permanent magnets generally work just fine - they just have to be bigger.
- dahauns 9y ago"Just have to be bigger"? I want lighter guitar amps that don't cost an arm and a leg, dammit! :)
- bsder 9y agoThen go solid-state. Inverter-based power supplies are sufficiently light that a guitar amp should only be the weight of the wood and the speakers. And, the speakers have to be a certain size to move the correct amount of air--so the copper coil is probably the limiting weight. It's remarkable how much air you have to actually move to get decent sound volume.
- dahauns 9y agoHm...sounds plausible from a physics POV, but maybe there's something else? Since, in practice (at least as far as I can speak from experience), old-school ferrit 15" speakers are ~7-8kgs, while you can get similarly specced neodymium speakers that weigh about half (3-4kgs).
- wycx 9y agoWigglers and undulators.
- Sean1708 9y ago> and those aren't used that much anymore There's still a lot of active research going into magnetic tape storage, I find it very difficult to believe research into hard drive storage is going to slow any time soon.
- mfrykman 9y agoMost commercial drones have 4 motors w about 12 magnets each. Some others: electric bikes, electric skateboards, power tools, blow dryers, iPad cases. If I recall correctly, one of the earlier iPhones was basically held together w rare earth magnets, with the screen module magnetically stuck into the case. Can't find info to verify this though, so take it w a grain of salt.
- saagarjha 9y agoWasn't this the iMac?
- falsedan 9y ago3M I guess
- joshmn 9y agoWould be my guess as well. Worth noting that the University of Minnesota (author) is no more than... 20 minutes from 3M HQ.
- sundvor 9y agoFusion reactors?
- agumonkey 9y agoMRI
- proaralyst 9y agoI thought MRI used superconducting electromagnets?
- Robotbeat 9y agoNot sure why you were downvoted. Some types of MRI use permanent magnets: https://en.wikipedia.org/wiki/Physics_of_magnetic_resonance_imaging#Magnet https://en.wikipedia.org/wiki/Physics_of_magnetic_resonance_...
- agumonkey 9y agoNo worries, for once I won't seek karma, I admit saying this without serious knowledge too so... Thanks anyway for the heads up. Very nice
- adrianN 9y agoElectromagnets
- deleted 9y ago[deleted]
- neltnerb 9y agoAgreed, 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!
- strainer 9y agoWindmills 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-metals-model-s https://forums.tesla.com/de_AT/forum/forums/no-rare-earth-me... [2] https://www.mathworks.com/help/physmod/sps/powersys/ug/wind-farm-using-doubly-fed-induction-generators.html https://www.mathworks.com/help/physmod/sps/powersys/ug/wind-...
- abricot 9y agoSure, the turbines themselves down't require rare earths, but that doesn't mean it isn't used for windmills. "In Vestas, rare earth elements are used in the magnets found in the towers of all new models of Vestas turbines" - Vestas[1] [1]https://www.vestas.com/en/about/sustainability#!material-use https://www.vestas.com/en/about/sustainability#!material-use
- strainer 9y agoRare earth magnets 'found in the towers' is a rather mysterious idea. I can only guess this is about relatively modest requirements of direction control motors.
- jessaustin 9y ago
- pg_is_a_butt 9y agoto the university, moron.
- Robotbeat 9y agoIndeed, Hyperloop Transportation Technologies (the crowdsourced one) said they'd use Inductrack technology for their version of Hyperloop: https://en.wikipedia.org/wiki/Inductrack 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 https://www.google.com/patents/US20100064929
- jcoffland 9y agoYes but maintaining a vacuum over long distances is a huge challenge.
- paulmd 9y agoAny public information on what Musk thinks he can get the leakage rates to? I assume the metric here would be something like cubic-yards-per-mile-per-day or something like that.
- grkvlt 9y agoOr acres per fortnight, perhaps?
- Xeoncross 9y agoI'll say, mine always gets caught going around corners or on chairs...
- Obi_Juan_Kenobi 9y agoIt's a 'soft' vacuum, so doesn't have anywhere near the difficulty of a 'hard' vacuum. IIRC the detailed specs of what they intend to do aren't out, so it's all just speculation.