Posted on 12/23/2015 12:40:15 PM PST by Red Badger
At left, a deformed sample of pure metal; at right, the strong new metal made of magnesium with silicon carbide nanoparticles. Each central micropillar is about 4 micrometers across. Credit: UCLA Scifacturing Laboratory
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A team led by researchers from the UCLA Henry Samueli School of Engineering and Applied Science has created a super-strong yet light structural metal with extremely high specific strength and modulus, or stiffness-to-weight ratio. The new metal is composed of magnesium infused with a dense and even dispersal of ceramic silicon carbide nanoparticles. It could be used to make lighter airplanes, spacecraft, and cars, helping to improve fuel efficiency, as well as in mobile electronics and biomedical devices.
To create the super-strong but lightweight metal, the team found a new way to disperse and stabilize nanoparticles in molten metals. They also developed a scalable manufacturing method that could pave the way for more high-performance lightweight metals. The research was published today in Nature.
"It's been proposed that nanoparticles could really enhance the strength of metals without damaging their plasticity, especially light metals like magnesium, but no groups have been able to disperse ceramic nanoparticles in molten metals until now," said Xiaochun Li, the principal investigator on the research and Raytheon Chair in Manufacturing Engineering at UCLA. "With an infusion of physics and materials processing, our method paves a new way to enhance the performance of many different kinds of metals by evenly infusing dense nanoparticles to enhance the performance of metals to meet energy and sustainability challenges in today's society."
Structural metals are load-bearing metals; they are used in buildings and vehicles. Magnesium, at just two-thirds the density of aluminum, is the lightest structural metal. Silicon carbide is an ultra-hard ceramic commonly used in industrial cutting blades. The researchers' technique of infusing a large number of silicon carbide particles smaller than 100 nanometers into magnesium added significant strength, stiffness, plasticity and durability under high temperatures.
The researchers' new silicon carbide-infused magnesium demonstrated record levels of specific strength—how much weight a material can withstand before breaking—and specific modulus—the material's stiffness-to-weight ratio. It also showed superior stability at high temperatures.
Ceramic particles have long been considered as a potential way to make metals stronger. However, with microscale ceramic particles, the infusion process results in a loss of plasticity.
Nanoscale particles, by contrast, can enhance strength while maintaining or even improving metals' plasticity. But nanoscale ceramic particles tend to clump together rather than dispersing evenly, due to the tendency of small particles to attract one other.
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.
To further enhance the new metal's strength, the researchers used a technique called high-pressure torsion to compress it.
"The results we obtained so far are just scratching the surface of the hidden treasure for a new class of metals with revolutionary properties and functionalities," Li said.
The new metal (more accurately called a metal nanocomposite) is about 14 percent silicon carbide nanoparticles and 86 percent magnesium. The researchers noted that magnesium is an abundant resource and that scaling up its use would not cause environmental damage.
Explore further: New 'high-entropy' alloy is as light as aluminum, as strong as titanium alloys
More information: Lian-Yi Chen et al. Processing and properties of magnesium containing a dense uniform dispersion of nanoparticles, Nature (2015). DOI: 10.1038/nature16445
Journal reference: Nature
The solution for guns that you want to be lighter, yet have the same strength, is Flash Bainite (a specially, though cheaply, processed steel). See http://nextbigfuture.com/2015/12/super-strong-flash-bainite-steel.html
Make the barrel and all components exposed to high heat out of Flash Bainite steel, and the rest can be made of anything at all. Maybe the 2 processes can even be combined?
I forget who said it, but some VERY bright and notable scientist once said that if a young scientist says that something is possible, listen to him; OTOH, if some old scientist says it is impossible, just ignore him. I guess that the old scientists were advising the government back then, but the bureaucratic imperative (grow or die) preserved the Patent Office.
I don’t think that anyone, save literal Communists, will ever make that assinine suggestion again.
I doubt we’ll ever get the space elevator idea to work, the forces just seem a bit too insurmountable. I think a more practical approach, like rail gun launchers, or dirigible launch platforms, will be the way to go.
I went to school with that guy. We called him "Jiffy Stiff".
IIRC, a space elevator has to be on the equator, so the first thing is location, location, location. Assuming a sea anchor point is pretty much out of the equation, and Africa is, well Africa. That leaves a small sector in northern South America.
An area where the political climate is as iffy as the tectonic activity. Interesting problem, no?
IIRC, likes can machine likes. So a silicon carbide tool should be able to machine it..................or :
http://phys.org/news/2009-02-scientists-material-harder-diamond.html
Wonder if same can be dome with aluminum, magnesium is 2.5 times higher price than aluminum.
Oh, how well I remember. I rebuilt my wife’s back in the early 70’s. But I think the finned cylinders were steel. I was just wondering if the weight was a big enough factor that they might go with a Mg block and sleeve it out - or if that would be needed. I’m guessing it still would be.
woohoo- metal toilet paper coming soon (did I say that out loud?)
Just say no go GMO metals.
Oh, when/if we develop the technology for a space elevator, brazil may be a superpower, who knows. Btw like your tagline- I’m a big Chesterton fan. Speaking of Chesterton- “Do you know how angels fly?...........They take themselves lightly!” And given the time of year.
The House of Christmas
There fared a mother driven forth
Out of an inn to roam;
In the place where she was homeless
All men are at home.
The crazy stable close at hand,
With shaking timber and shifting sand,
Grew a stronger thing to abide and stand
Than the square stones of Rome.
For men are homesick in their homes,
And strangers under the sun,
And they lay on their heads in a foreign land
Whenever the day is done.
Here we have battle and blazing eyes,
And chance and honour and high surprise,
But our homes are under miraculous skies
Where the yule tale was begun.
A Child in a foul stable,
Where the beasts feed and foam;
Only where He was homeless
Are you and I at home;
We have hands that fashion and heads that know,
But our hearts we lost – how long ago!
In a place no chart nor ship can show
Under the sky’s dome.
This world is wild as an old wives’ tale,
And strange the plain things are,
The earth is enough and the air is enough
For our wonder and our war;
But our rest is as far as the fire-drake swings
And our peace is put in impossible things
Where clashed and thundered unthinkable wings
Round an incredible star.
To an open house in the evening
Home shall men come,
To an older place than Eden
And a taller town than Rome.
To the end of the way of the wandering star,
To the things that cannot be and that are,
To the place where God was homeless
And all men are at home.
.........GK Chesterton
Can it be welded? What about flammability?
Thanks for the Chesterton insert. Hadn’t come across it before.
Very Merry and joyous Christmas greetings.
Thanks Red Badger.
Manages a passivation similar to aluminum.
Or any metal, since this particular alloy is just silicon carbide nanoparticles infused within the magnesium structure. The possibilities are endless................................
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