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Science Technology

UCLA Creates Super-Strong, Super-Light Metal (ucla.edu) 70

An anonymous reader writes: Engineers working on planes, rockets, and other vehicles are always looking for new metals to make their creations lighter and stronger. A new invention from UCLA demonstrates "record levels of specific strength — how much weight a material can withstand before breaking — and specific modulus — the material's stiffness-to-weight ratio." The metal is mostly (86%) magnesium, but infused with an even dispersal of ceramic silicon carbide nanoparticles (abstract). A key part of their work was preventing the nanoparticles from clumping, since they attract each other if left alone. "To counteract this issue, researchers dispersed the particles into a molten magnesium zinc alloy. The newly discovered nanoparticle dispersion relies on the kinetic energy in the particles' movement. This stabilizes the particles' dispersion and prevents clumping."
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UCLA Creates Super-Strong, Super-Light Metal

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  • The metal is mostly (86%) magnesium

    Not sure I want anything made of this material in my house or vehicle.

    • The metal is mostly (86%) magnesium

      There are some inherent risks, but I doubt it would be all that easy to get it to start burning in most typical consumer applications.

      On the downside, magnesium can be bear to put out when it gets going.

      • Re:Don't want (Score:5, Insightful)

        by FatdogHaiku ( 978357 ) on Friday December 25, 2015 @12:59PM (#51182309)

        On the downside, magnesium can be bear to put out when it gets going.

        That probably takes the understatement of the thread award...
        http://www.popsci.com/diy/article/2008-06/let-burning-metals-lie [popsci.com]

        • LOL, too bad I used up all my mod points... I'm guessing that this material would not be allowed on passenger carrying craft without being stabilized in some way...
          • That would be passenger carrying trains and passenger-carrying bicycles?

            Magnesium has been used repeatedly as a structural metal in aircraft since ... world war 2, at least.

            Sure it's a pig to put out. But by the time that the structure of a plane is burning, you're in a massive multiple fatalities situation (like, survival happens by luck, not planning, judgement or personal actions). and you've already lost structural integrity and control of your fuel.

            • Two words: Belly landing.

              • Don't put flammable materials in the area that will come into violent contact with the ground in a belly landing. E.G. put your fuel in tanks ABOVE the grounding line. (Been done for decades.) Don't put flammables in places like engines that will be spinning rapidly when they come into contact with the ground. Don't use PVC (or other toxic-smoke producers in the passenger cabin.

                None of these are either rocket science, or news.

                If you have a strong, stiff material, that is no reason to NOT use it for wing s

        • Re:Don't want (Score:4, Informative)

          by Megol ( 3135005 ) on Friday December 25, 2015 @03:15PM (#51182739)

          No that was the "... I doubt it would be all that easy to get it to start burning ..." bit that was the real understatement.

          Magnesium in bulk itself is extremely hard to get burning - think spending some minutes with an acetylene gas welder. But the alloys that are used in practice also includes ingredients (commonly calcium) that makes it even harder.

      • But most consumers want an indestructable Wolverine endoskeleton, so this really is a deal breaker.

      • Re:Don't want (Score:5, Interesting)

        by TWX ( 665546 ) on Friday December 25, 2015 @01:08PM (#51182339)
        Uh, you would be wrong [youtube.com]...

        My wife and I had one of the grilles in this series. We got the recall notice right after thoroughly cleaning the grille for the first time. Normally the inside of the chamber is protected by a layer of oxidation, but a thorough cleaning scrapes the oxide layer off and exposes fresh magnesium. Ours didn't catch fire, but after we got the recall notice we looked into it and apparently the first heavily-documented case of the grille burning was after the owners thoroughly cleaned it and probably exposed fresh magnesium right before using it again.

        Magnesium is used successfully for other applications, but usually with the fire-risk considered an acceptable tradeoff. Engine blocks, with steel liners for the cylinder walls and with aluminum cylinder heads so that the magnesium isn't directly exposed to flame, and in wheels that should be safe unless a tire failure results in a skidding bare wheel scraping against pavement are both common in racing. The very term, "mag wheel," is based on the use of magnesium wheel, even if most are now aluminum for street-legal uses.

        For the right applications this alloy could be very good. Just don't make barbecue grilles out of it.
        • Uh, you would be wrong [youtube.com]...
          For the right applications this alloy could be very good. Just don't make barbecue grilles out of it.

          So, actually, I'm not wrong. :)

          For most applications it wouldn't be an issue. I can't remember how many times my cellphone has caught fire, maybe because the number is "0". Yes, yes Lion batteries, danger, etc etc etc but it just doesn't really happen all that much in real life. But it would be fine for a lot of the things I mentioned- knives, antennas, bike frames, most tools (ever had a hammer catch fire? Me neither.), tablet cases, etc etc.

          So yeah, there are definitely places you wouldn't want to use it,

        • I can't imagine why anyone would make a grill out of magnesium. Same goes for car parts. Aluminum alloy is much cheaper, not flammable, and nearly as lightweight. Maybe mag wheels made sense in the past before they figured out how to make really good aluminum wheels, but these days forged aluminum wheels are pretty hard to beat and don't cost *that* much (and cast ones are pretty decent and downright cheap). And everyone makes engine blocks out of aluminum these days.

          • by TWX ( 665546 )
            Again, in actual race cars a few pounds matter. If a cast-iron bare smallblock engine block weighs about 150lb, and an aluminum bare block weighs 100lb, if a magnesium block weighs 90lb, that weight difference would be pursued, along with hollow cams, a forged lightweight crank, hollow pushrods, and all sorts of other performance parts.
    • The metal is mostly (86%) magnesium

      Not sure I want anything made of this material in my house or vehicle.

      (I just had to look it up. Damn my OCD!)

      According to the Wikipedia article on Magnesium rims [wikipedia.org], the bulk metal is difficult to ignite. This mirrors my own experience - it's hard to ignite a strip of magnesium for a chemistry demonstration.

      (From the article: Mag rims are no longer made, not because they're dangerous, but because they tend to pit and crack and need constant polishing.)

      It seems likely the extra 14% would make the alloy less combustible than raw Magnesium. If you're already on fire hot enough to

      • Re:Probably safe (Score:4, Interesting)

        by nojayuk ( 567177 ) on Friday December 25, 2015 @01:42PM (#51182431)

        the bulk metal is difficult to ignite.

        Magnesium alloys are very good heat conductors so applying flame to one area of a large solid piece of magnesium alloy won't ignite it, any more than, say, aluminium alloy materials as the heat is ducted away from to contact point. On the other hand magnesium powder, thin ribbon or wire will burn without too much effort.

        Acquaintances of mine who put some magnesium-alloy aircraft wheel hubs in a bonfire were somewhat disappointed by the lack of performance until one of them rigged up a feed of pure oxygen into the bonfire at which point they lit off quite nicely.

        • Rigging up a direct feed of pure oxy into any convenient bonfire sounds like a way to make it "light off quite nicely".

          [Puts another entry onto the the bucket list. Somewhere above "deal with the 12kg of mercury in the shed".

      • Re:Probably safe (Score:4, Interesting)

        by Ungrounded Lightning ( 62228 ) on Friday December 25, 2015 @02:44PM (#51182625) Journal

        According to the Wikipedia article on Magnesium rims, the bulk metal is difficult to ignite. This mirrors my own experience - it's hard to ignite a strip of magnesium for a chemistry demonstration.

        The power tools were off limits without supervision when I went to high school. This apparently became a hard rule a few years before, when the shop teacher walked in on a student who had a magnesium automotive wheel in the lathe, and was up to his knees in magnesium ribbon, in the form of long, curly shavings.

        Yes, it's hard to light, but ribbon is much easier to get going than a block, and there's a lot of heat from metal working. (I hear one way to light a block is to curl up a tapered shaving and light the end of it.) Once it's lit it's nearly impossible to extinguish. (It burns in water, for instance, sucking out the oxygen and releasing hydrogen. It burns in carbon dioxide, similarly releasing a black cloud of carbon dust. Hit it with either of those types of extinguisher and it just gets more violent.) If the kid had managed to light those shavings they'd have tangled in his pants and followed him around as he tried to escape.

        (I haven't tried it, but I bet an electric arc would light off a block of magnesium just fine...)

        This stuff might be somewhat safer: I'd expect the nanoparticles to interfere with making long, thin, shavings.

        • Try to put out the fire with fluorine gas. That's when the escapades really begin!

          Nothing prefers fluorine over oxygen, aside from the alkaline earths (column II).

          Then again, if you're spraying fluorine gas on a fire, then you should not be allowed in a lab. That would kill the whole town, just from the fluorine release alone.

          • FOOF is your friend for problems like this.

            If you can't get hold of FOOOF.

            Above are formulae, not sound effects.

    • It is my understanding that some ladders are made of magnesium. The biggest drawback that I see, regarding common use, is the flammability factor. If a car built of this stuff gets on fire, the fire is soon going to get spectacular.
      • Magnesium alloys require 1700-2100C to ignite, of you've already got a fire that hot the car is already a total loss and the only additional damage might be deformed cement that a normal gas and steel fire might not have damaged, blacktop is shot either way.

    • Not sure I want anything made of this material in my house or vehicle.

      I DEFINITELY don't want any of it in an implant - at least until they figure out how to make it using something other than aluminum in the initial unclump-the-nanoparticles step.

      Aluminum inside the body is HORRIBLY toxic. It was the cause of the alzheimers-like "dialysis disease" that severely limited the time the early artificial kidneys could be used - before they figured that out and changed the material of the tub holding the water t

      • Most things inside the body are toxic; we have immune systems to handle foreign bodies, and these systems will attack just about anything artificial. However, titanium is an exception, which is why so many surgical implants are made out of it. It's completely biocompatible, and bone will even grow into it.

        So if you want an artificial endoskeleton, just use titanium. It's not as indestructible as adamantium of course, but it's a lot stronger than your normal bones.

    • by Megol ( 3135005 )

      I sure hope you have no aluminium nor any solid H2O at home! That is rocket fuel! ...
      Or perhaps you shouldn't be afraid of simple things that aren't dangerous? Be afraid for plastics (often ignites easily and generates nasty smoke), fabric (easily ignited, some likes to melt and fuse with skin etc.) and wood instead? Or even candles - one of the most common reason for fires at home. Those things that actually can be a danger.

    • It's an alloy. I don't know about this particular alloy, but alloyed metals can have radically different properties from their base components. Take a look at stainless steel for instance: it's made of iron, carbon, and chromium. Iron is of course the largest constituent (I'm guessing around 80%). Iron is ductile, and also ferromagnetic: you can stick magnets to it. It also has a tendency to rust really, really easily. Now you add a bunch of chromium (the grades with more chromium are more "stainless"

  • Very cool (Score:4, Interesting)

    by JustAnotherOldGuy ( 4145623 ) on Friday December 25, 2015 @12:41PM (#51182269)

    This stuff has limitless possibilities. Everything from knives to bumpers to bike frames....the list of potential applications is endless.

    Better cellphone cases. Better engines and electric motors. Better ballistic armor. Better tools. Better antennas. Better vehicles that fly/float/roll.

    • by hey! ( 33014 )

      This stuff has limitless possibilities. Everything from knives to bumpers to bike frames....the list of potential applications is endless.

      Well, steel has one under-appreciated quality that this material (being partly ceramic) probably doesn't have: a benign failure mode -- at least if it hasn't been hardened. This makes it an excellent material for something like bumpers where it will absorb energy by continuing to deform instead of shattering.

  • Screw carbon fiber. By the way I'm also still waiting for my structural aerogel racing bike frame. All the above will probably will arrive in the mail the same day my hoverboard does. :-/
  • How strong?
    How much does it cost?
    Can it be scaled up enough to build cars, bridges and buildings out of it?

    • Can it be scaled up enough to build cars, bridges and buildings out of it?

      I think the real question is whether it should be used for these purposes. If you do decide to go ahead and get a car made of this alloy please get a dash cam with wireless streaming because you may end up with a spectacular youtube video, albeit is short sone since the camera probably won't take long to melt!

    • How strong?

      Super-.

  • That would make it even lighter. And I don't know why they call it a metal, it is a composite, a meta-material surely?
    • by Anonymous Coward

      The main author had already published a paper using graphene in 2012.

      http://www.sciencedirect.com/science/article/pii/S1359646212001868

      Scripta Materialia Volume 67, Issue 1, July 2012, Pages 29–32

    • That would make it even lighter. And I don't know why they call it a metal, it is a composite, a meta-material surely?

      It's a metal-matrix composite, which have been around for decades.

  • Is it transparent?

  • I'm so excited that modern science has started to use nano-particles. In the past, we'd just use molecules and atoms in chemistry and metallurgy.

    From the perspective of the Silicon nano-particles, that Magnesium must be HUGE.

  • by Required Snark ( 1702878 ) on Saturday December 26, 2015 @01:24AM (#51184999)
    This is definitely a breakthrough, but it still might have some problems moving into general use. The fact that 14% of the material is silicon carbide could lead to some real manufacturing headaches. Remember that silicon carbide is the material of choice for grinding wheels and sanding. So what happens when you try to drill a hole in this stuff, or grind or polish it? What does it take to machine?

    There is also the question of how to weld it. Does it make a strong weld with the dispersed embedded particles, or is welding a problem?

    As for all the speculation about it being a fire hazard, the effect of the silicon carbide on combustion is very unclear. It could make the material less flammable because the silicon carbide will not contribute to combustion.

    Still, it seems likely that this material, or something using similar technology, will make it into general use. Stronger and lighter with reasonable cost will always pay off.

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