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MIT Unveils New Material That's Strongest and Lightest On Earth (futurism.com)
A team of MIT researchers have created the world's strongest and lightest material known to man using graphene. Futurism reports: Graphene, which was heretofore, the strongest material known to man, is made from an extremely thin sheet of carbon atoms arranged in two dimensions. But there's one drawback: while notable for its thinness and unique electrical properties, it's very difficult to create useful, three-dimensional materials out of graphene. Now, a team of MIT researchers discovered that taking small flakes of graphene and fusing them following a mesh-like structure not only retains the material's strength, but the graphene also remains porous. Based on experiments conducted on 3D printed models, researchers have determined that this new material, with its distinct geometry, is actually stronger than graphene -- making it 10 times stronger than steel, with only five percent of its density. The discovery of a material that is extremely strong but exceptionally lightweight will have numerous applications. As MIT reports: "The new findings show that the crucial aspect of the new 3-D forms has more to do with their unusual geometrical configuration than with the material itself, which suggests that similar strong, lightweight materials could be made from a variety of materials by creating similar geometric features."
Claiming it can replace steel means it has not only better tensile strength, but also compressive strength, low brittleness, and similar ductility and hardness.
Glass is stronger than steel, in one direction only. It's not used in structural engineering though. Steel is just so versatile that so far not any material has matched it.
But, impressive research and I hope they keep going with it.
I doubt *any* material will completely replace steel. The particular properties of steel, it's strength combined with easy machining and reasonable cost will always be right for some applications, much as brass is still used. Steel didn't completely replace brass, carbon fiber didn't completely replace steel, and this new material won't completely replace any of it's predecessors.
However, steel allowed us to make things that couldn't be made with brass, carbon fiber works better than steel for some things, and this new material will be the best choice for some things.
There are very few application where carbon fiber is better than steel, because it lacks most of the properties of steel. It's not elastic, it's not machinable, it's brittle, it doesn't wear well. There seems to be no replacement for steel used structurally (including this stuff), for tool steel, for anything that needs to flex a bit in normal use, etc.
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Imagine a net (block?) of this material. IF (and it's a very big if) it could be made large enough IN SPACE, then it could "capture" (by absorbing the impact) space junk. It might need to be hooked up to a low thrust but high efficiency ion drive to compensate for the slow loss of momentum from the impact; it needs to stay in orbit (and to change orbits if it's going after multiple large pieces).
Of course, as mentioned, the real key is can they manufacture the graphene pieces AND put them together in the 3D structure IN SPACE. Being able to create this material out of a (solid?) block of carbon (graphite) is probably essential. Otherwise the density of the structure might be too low to be launched from earth; the low density which might make it ideal for many applications on earth would be a hindrance if it required a huge fairing for the launch vehicle (imagine a blimp on top of a rocket). However, this low density is critical for its success as a space "sponge", it would allow a small mass to subtend a very large volume; essential if we're ever going to clean up the many many small fragments of space junk (and not just the big ones).
Of course, IF they can make this in space there are many space construction applications which could be practical. Would it dramatically reduce the cost of an "O'Neil space cylinder" for example? The greatly reduced mass requirements coupled with the (hopefully) greatly reduced launch costs from reusable launchers (go Space-X!) might allow really large structures to be built. (I guess you'd still need "soil" and volatiles from asteroid or lunar mining).
(A similar solution would be to use in space produced aerogels. The problems of making aerogels in space if they require supercritical carbon dioxide as a working fluid may be too great though.)
Just an early morning rant here in Vietnam, probably had too much coffee.
The material in question is graphene, which they did not create or unveil.
The structure in question is theoretical, and they have not made it nor do they have any real plans or methodology to do so.
They made a mathematical model and then 3D printed a PLASTIC model in the same shape.
They then crushed the plastic model and noted that it was pretty strong given its density, just as they predict a graphene structure in the same shape to be.
They're not creating the graphene structure, and a macro version of the structure in plastic may or may not exhibit similar properties as a true version made of ultra thin graphene.
https://youtu.be/VIcZdc42F0g
I'm all for improved materials, but let's not make shit up, futurism.com .
Here's the most relevant bit:
The team was able to compress small flakes of graphene using a combination of heat and pressure. This process produced a strong, stable structure whose form resembles that of some corals and microscopic creatures called diatoms. These shapes, which have an enormous surface area in proportion to their volume, proved to be remarkably strong. “Once we created these 3-D structures, we wanted to see what’s the limit — what’s the strongest possible material we can produce,” says Qin. To do that, they created a variety of 3-D models and then subjected them to various tests. In computational simulations, which mimic the loading conditions in the tensile and compression tests performed in a tensile loading machine, “one of our samples has 5 percent the density of steel, but 10 times the strength,” Qin says.
The video is about testing 3D plastic models. Exactly what they have achieved is unclear to me. Do they have plastic in a configuration 10 times the strength of steel? Did they 3D print in steel, but didn't show it in the video? Did they extrapolate from a plastic model to say that if they'd made it of steel it would be 10 times the strength of steel? Did they use a computer model to say that if they could make the optimal graphine configuration it would be 10 times strength of steel?
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Steel has many conveniences that will likely keep it around for a very long time as a general purpose construction material. But I also suspect that for any specific application it will be radically outperformed by a custom-build structure from micro- and nano-engineered materials such as these. The price of course will be a key differentiator for most applications, and perhaps ease of recycling. So it may be a long time before they become desirable outside of particularly high performance applications.
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According the the article they only have a theoretical model for the material and the claim that it is the strongest material known seems to be based solely 3D printed models agreeing with a computational model of the material. This is no grounds whatsoever to claim that this is the "worlds strongest material". It's a promising start which might lead to that but until you have actually built the material and measured its properties you cannot claim the discovery.
We did not claim the Higgs discovery in the 1960s based on Higgs' theory we needed to wait until there was experimental evidence showing it was correct. The same applies here: there is no guarantee that some effect they have not modelled is important and means the material does not behave as they expect it to. A macroscopic plastic model is not guaranteed to behave the same due to the larger quantum mechanical effects at smaller scales. In fact so far they do not even know yet whether it is possible to build the material - so lets cut the hype and have them make their claim when they actually have the material in hand and confirmed it really does perform as they predict.
Er, are you joking? Bullet casings? How many hundreds of millions of those are made every year???
my 3d printer's nozzle is brass. So are some motor/generator brushes. It has its uses.
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Brass is considered where you want better corrosion resistance than steel (plumbing fittings), shine (visible hardware, knobs), lighter weight (musical instruments) or a softer material (non-scratching, non-sparking tools), or a bit of self-lubrication (locks and keys).
I have many hobbies and most end up using brass for something. I do electronics, where brass terminals are used for connections. I do model aircraft, which use brass rods because they are lighter than steel. I do pyrotechnics, where steel is forbidden due to sparks. Very often, if steel isn't a good choice for any reason, brass is a likely alternative.
Of course that doesn't mean brass is *better* than steel. Often you want the harder metal. Each has their own uses.
> because it lacks most of the properties of steel. It's not elastic, it's not machinable, it's brittle, it doesn't wear well.
Maching carbon fiber is a bit different from machining carbon steel, just like machining stainless steel is a bit different. It most certainly is machined. Actually in some ways the machining of carbon fiber is very similar to stainless steel.
Carbon fiber is slightly MORE elastic than steel. The modulus of elasticity is about 150Gpa with steels ranging about 150-180Gpa.
"Brittleness" (KIc) can't be directly compared since carbon fiber is a composite, but generally cracking is localized - it's not particularly brittle.
"Doesn't wear well" isn't scientifically confined, so I can't give hard numbers for that. We can note that the two major typesnof fiber tows and the many available resins allow a designer to choose the wear properties appropriate for the application.
The big advantage steel has over carbon fiber is cost. While the cost of carbon fiber has reduced significantly in the last ten years, it's still $10/pound in quanity. That definitely matters if you need thousands of pounds of it. It's not too significant if you need less than a pound of material for something you're already spending $30+ on.
Spectacularly wrong. Carbon fiber is about as brittle as china. It has very little toughness.
It's a bit depressing to see this volley continue back and forth with no one mentioning the fact that the "carbon fiber" you're referring to is... plastic. Plastic with carbon fibers added to strengthen it, just like fiberglass refers to plastic with glass fibers added to strengthen it.
From this, there are two key points to make in this debate that so far haven't been made:
1. The properties of carbon fiber depend largely on the properties of the material its being added to. There are a wide variety of polymers out there and, in principle, you could probably put it in concrete, or maybe even a cold-forged metal.
2. The parallels between carbon fiber and whatever this new material is are inconsequential if the new material is something that can be used directly and not as an additive.
The article is shockingly unhelpful in clarifying this second point, and it even cryptically adds that the geometrical techniques here could be used directly with non-carbon materials, which doesn't make a lot of sense given the unique molecular geometric properties of graphene (clearly show in illustrations in the article) are dependent on the chemical properties of carbon.
Also becuse of the copper in it brass has antiseptic properies. Something the victorians discovered by chance which is why hospitals used to have brass door knobs and handles all over the place. Of course these days stainless steel is used along with a boatload of disinfectant. Medicine sometimes regresses unfortunately.
This is pure carbon which is really NOT something you want to build any kind of structure out of if its likely ever to come near a naked flame or source of heat
When was the last time you lit a diamond on fire? Pure carbon burns at 4890F. For comparison steel melts at around 2750F.
Don't confuse carbon with carbon based products like coal. Coal is a composite material that has oxygen, hydrogen, sulfur and nitrogen. It's no where close to being pure carbon.
Why? At 10x the strength, and 1/20th the density, the breakeven point would be $60,000/ton to get equal strength for equal cost. That will still probably not be achievable any time soon, but you also have the added benefit of your structure weighing 1/200th of what it would have if made from steel, a huge benefit for anything that needs to be accelerated, or to support it's own weight.
--- Most topics have many sides worth arguing, allow me to take one opposite you.