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Science Technology

A Building Material 12 Times Stronger Than Steel 73

Posted by timothy from the how-about-for-pogo-sticks dept.
nm1m writes: "For the last few months I have been following with some interest a few stories (story link may not work) in the school newspaper about a new structural technology being developed at BYU. It is called PYRAmatrix, and is 12 times stronger than steel, yet less than 10 percent the weight of steel. A 47 foot cylinder of this stuff, 16 inches in diameter and weighing just 47 pounds, can support almost 4 tons. It seems to have obvious applications in aerospace, electricity utility poles, radar and communication towers, and just about any structure that needs exceptional strength. An interesting press release with facts and figures can be found here. Photos can be found here." The link worked for me -- and reminded me of the plastic-walking scene in Sabrina .
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A Building Material 12 Times Stronger Than Steel More

A Building Material 12 Times Stronger Than Steel

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  • Every Silver lining has a cloud, and I am wondering about the amount to time that this material lasts. It's fine for it to be a super light polymer, and have the stringth of Cowboy Neal, but how long will it be before it starts to lose it's stringth? How long before it would crack like Jon Katz?

    I would hate to live near a power pole made of this stuff, after it had been up for a couple of years.
    • I would hate to live near a power pole made of this stuff, after it had been up for a couple of years.

      I see what the angle is now - this is a semi-disposable technology. Instead of charging once on installation, you get annual repair bills. Sounds pretty lucrative to me.

  • I'm beating my head against a wall trying to figure out why anyone wouldn't buy this

    This hardly seems an objective description of a product. It looks like a good idea - I love the idea of a one pound bike frame - but they should lay of the hyperbole a little.

  • This looks like pretty cool stuff, but it still isn't nearly as strong (or as light weight) as Goat-produced spider silk. [forbes.com]
    • A question about this goat spider silk - does spider silk scale linearly? What I mean is, for example, multicellular organisms don't scale linearly. A human that was six times as tall would crush it's legs to splinters if it tried to stand up, and fleas or other insects can jump or fall many hundreds of times their own height safely, unlike a human scale animal. What I wonder is if spider webs are similar - amazing properties on a spider scale, but pretty pathetic at a larger scale.

      Also, watch out bringing up goats around here...

      • Silk is very strong on the large scale too, if you weave it together in a rope. Obviously like any other fiber it can only handle tension not compression. Pales in comparion to nano tubes obviously :)
      • It could support spider-man, and hes an average sized human. It didnt seem all to strong when trying to hold that trolley. But I think that was more a problem of sticking to it then tensile failure.

        Hope that helps

        veramocor
      • If you scale something in only one or two dimensions, then yes, the results will be horrible. Of course a person 6 times taller (but all other dimensions normal) will be in bad shape. However, if you scale it in all dimensions, they will do just fine--until they try to walk down main street and take a 6kV power line in the crotch.

        Ditto on spider silk. Increase the length 100 times and yes, it's useless. Increase the length AND the girth 100 times, and you have something that could give fullerines a run for their money.

        • If you double a person in every dimension, you end up with 8x the original volume (2^3). However, the strength of a person's bones are proportionate to the cross-sectional area, which is only 4x the original area. And that's why a giant-sized human would grind his legs into powder with the first step.

        • >However, if you scale it in all dimensions, they will do just fine--until they try to walk down
          >main street and take a 6kV power line in the crotch.

          Wrong. Expanding dimensions doesn't work because the physical size isn't the only consideration. Area expands as the square of the size, volume as the cube.

          Increase the length and girth 100 times and the weight would increase 100^3 or 1,000,000 times. Your leg bones would snap like toothpicks.

          Two examples of "movie myths":

          Giant insects would be crushed under the weight of their own exeskeletons.

          People the size of insects would have to eat several times their own body weight in food just to keep their body temperature constant.

          ObTopicRef: A previous poster was right, strength in compression is only useful in specific applications. Take aerogel, for example. It can support 100 times its own weight in compression. Handle it the wrong way and it crumbles to itty bitty pieces.
          • the best example i ever read explaining this "phenomenon" is the stick figure cow example. draw a cow with a 2" dia. circle for a head, a 1" stick connecting head to body, a 4" dia. circle for the body, and 4 2" stick legs. at this size, everything is relatively strong enough to support the weight it needs. double the size of the cow, and all of a sudden you have a 4" circle for a head, being supported at the end of a 2" neck, which is somthing like 4 times the original volume, with more leverage, being farther away from the head. snap goes the neck and the head bursts as it falls the (now doubled) 4" to the ground. legs collapse under the immense weight of the body, for same reasons as explained about head.
          • Actually you have the body temp thing wrong. As the size of the body increases, the percentage of surface area per body mass goes down. There was an article somewhere that talked about this w.r.t. to dinosaurs. The smaller you are the faster you lose body heat.

        • If you scale something in only one or two dimensions, then yes, the results will be horrible. Of course a person 6 times taller (but all other dimensions normal) will be in bad shape. However, if you scale it inal all dimensions, they will do just fine--until they try to walk down main street and take a 6kV power line in the crotch.

          You are absolutely and completely, without an ounce of doubt, dead wrong. I think ;)

          From my first year civil engineering course (for non-civil engineers), Lecture 27 entitled The Design of Bones and Towers. A person who is 6 times bigger (with intelligent scaling) than an average human would snap his tibia with his first step. From what I can decipher from my poorly written and deteriorating notes, the basic problem is that area/volume ratios change when you scale a design. Your bones, at the same relative thickness for a 30 foot tall person woudn't be able to withstand the scaled up forces. For anyone with more intuition in this area, please feel free to post a more intelligent analysis.

      • A question about this goat spider silk - does spider silk scale linearly? [...] What I wonder is if spider webs are similar - amazing properties on a spider scale, but pretty pathetic at a larger scale.

        All materials obey the square/cube law (strength scales as the square of the scale, weight as the cube). The important number for cables is tensile strength per unit area. This number is independent of scale.

        Spider silk and many other more common polymers have a tensile strength comparable to or greater than that of steel, while weighing much less. The down-side is usually that they stretch more when force is applied (lower elastic modulus).

    • Apples and oranges.

      Spider silk has a very high tensile strength, meaning that you can hang things with it. PYRAmatrix has a very high compression strentgh, meaning you can set things on top of it. Using spider silk to build pillars is a lot like pushing a rope. Now you could use spider silk along with a resin to create a composite material. You could even use this material to create a very strong PYRAmatrix.

    • This looks like pretty cool stuff, but it still isn't nearly as strong (or as light weight) as Goat-produced spider silk. [forbes.com]


      Yeah, and it's not as good a conductor as copper. What's your point? Spider silk can't be made into rigid structures, right?

    • yes, but this patent is for a geometry, not a material.

      So you could use goat spider silk in your composite structure, using their geometry.

  • Material and structure (Score:4, Interesting)

    by heikkile ( 111814 ) on Monday June 03, 2002 @09:12AM (#3630605)
    To my untrained eye it seems like they have created a lattice pattern in some sort of polymer. Then they compare its behaviour to steel tubes. At least here in Denmark, most tall poles are already lattice structures, usually of steel. I wonder if this miracle material would perform well in a traditionally shaped lattice or if their new miraculous lattice would work even better with conventional steel?
  • Now this [pyramatrix.com] is a great advertising picture. "See, even a girl can carry a 47 foot long pole of pyramatrix!"

  • press release? (Score:5, Interesting)

    by b_pretender ( 105284 ) on Monday June 03, 2002 @09:14AM (#3630624)
    The linked story seems more like a press release rather than a study of the material.

    It leaves out important facts, such as...
    ...strength is not the only important material property. The images only show this strength in compression.

    Is this material resiliant? Strong in tension or compression? Does it shear easily?

    ALL of these properties matter if you are going to use it. Usually, the Aeromet steels, super carbon composites and other superstrong materials suffer from poor non-strength properties, rendering them useless in most situations.

    Imagine your super material 2 lb bike frame that chips away because it is so brittle that rocks chip off peices, or is too rigid because the material has no elastic modulos.

    • Also, how it performs in temperature extremes. Remember Napoleon's troops had tin buttons and that tin becomes quite brittle at extremely low temperatures (like you might experience when marching to Russia). It's hard to walk and carry a pack and rifle much less fight when you're pants are falling off and you are also trying to keep your coat closed.
    • You obviously didn't read their FAQ here [pyramatrix.com]
    • In fact, when speaking of structures, 'strong' is almost entirely meaningless without qualification. Which is 'stronger', balsa wood or cast iron? And why wouldn't you make a model glider out of cast iron? There are a whole range of properties that matter, more usefully defined by stiffness, toughness, hardness, isotropy, thermal and chemical stability, density, etc.

      For a couple of really good books on the subject, try J. E. Gordon's "Structures" and "The New Science of Strong Materials" (See this page for a very brief review of Structures [nous.org.uk]. The books are quite old now, but the basic principles haven't really changed.

  • no "less than" or "more than" please (Score:1, Informative)

    by Anonymous Coward
    Less than 10% can mean anything from 0% to 10%. It's shorter and more precise to state that it's 9% the weight of steel.
    • You have a point. Thanks. -nm1m

    • Less than 10% can mean anything from 0% to 10%. It's shorter and more precise to state that it's 9% the weight of steel


      Since it's a structure and not a pure material, it's not precisely amenable to such analysis. As they say in the company website, the weight ratio of a pure steel tube to a PYRAmatrix strut depends on the size and shape of the strut in question. Apparently the structure is more efficient and thus has a better weight savings over steel at larger diameters.

      So you could say something like "it's 9% the weight of a steel strut 200mm in diameter with a load limit of 2000kg", but you couldn't give a single figure for all cases.

      Furthermore, they apparently make this stuff out of more than one different material; I saw both glass and carbon fiber product listed on the site. It's safe to assume that different materials will result in different properties relative to steel in the final product.

      So specifying a range like "less than 10%" is probably a perfectly valid generalization, as long as it's true for the majority of applications.

  • Oh yeah, great pictures... (Score:4, Funny)

    by Tom7 ( 102298 ) on Monday June 03, 2002 @09:15AM (#3630634) Homepage Journal
    These MS Paint [pyramatrix.com] jobs remind me of "all your base are belong to pyramatrix" or something...
    • Yeah, seriously, it looks to my eye like all of the pictures showing a real application (as opposed to someone holding it) are doctored. I can understand that, but it really doesn't help their credibility to pass off "simulated" pictures as real. Especially this one [pyramatrix.com], but also this [pyramatrix.com] and this [pyramatrix.com].

      Also, they mention that it costs less than similar fiber-composite structures, but that isn't really saying much since most composite materials are very expensive compared to steel/concrete/wood/aluminum/etc. It seems to me that it will take a lot of development to get the cost anywhere close to that of the traditional solutions. Sure the light weight is great, but it all comes down to cost, unfortunately. Now, if the lighter weight means that builders can save money on installation methods, then that might be a way to offset the higher material cost.
  • "The revolutionary idea is not the material used to make the form, but the structural design itself."

    It's a new building structure, not a new building material. It may not even be a truely new structure at that, at least similar designs have been used for qite some time.

  • This looks like cool tech. The pictures on the site are definatly bogus - But who knows, they are based in utah so being land locked prolly has them being a bit loopy. The matrix of triangles makes me worry since a break of one component would weaken the overall structure many more times over than a geometricly simplier structure made out of steel. Make sense? I like those cute little bar graphs on the site, unf unf.

  • Sweet. (Score:5, Funny)

    by TweeKinDaBahx ( 583007 ) <tweek&nmt,edu> on Monday June 03, 2002 @09:52AM (#3630910) Homepage Journal
    Now we can build 10,000 unit subdivisions in the desert at half the cost! Won't it be grand when we're all out of water?! I CAN'T WAIT!

    (Yeah, this is a bit paranoid BTW, but I live in new mexico so give me a break. EL VADO LAKE is a mud hole and I didn't catch any fish this weekend so I'm bitter.)
    • I agree.
      I live in San Diego, and driving over the San Diego "river" is a joke. There hasn't been any water in it in my 21 years of life. Most of the times, there isn't even any mud.

  • Patented the triangle!!! (Score:3, Funny)

    by walt-sjc ( 145127 ) on Monday June 03, 2002 @10:16AM (#3631107)
    Yes, our patent office is doing it's job. They have granted a patent on the triangle! This is great news. I'm going to go out and patent the square! There's money to be made... Muahahaha! All Your Square R Belong To Me!
  • Now this is what patents are for. Kudos!

  • eh? (Score:3, Interesting)

    by v4mpyr ( 185039 ) on Monday June 03, 2002 @01:56PM (#3632936)
    Interesting enough, however I don't see this being a widespread replacement for steel unless it can be easily cut, rolled, bolted, welded and whatnot. I used to work for a company that developed structural steel detailing and fabrication software and can say from experience that making a connection between two pieces of steel is not exactly a trivial task. This structure just doesn't look like it would easily lend itself to building anything of significance other than poles.
    • This thought occurred to me as well. The major stumbling block that I see is how to connect two of these matrixed-carbon poles together.

      If I wanted to build a gigantic geodesic dome [cjfearnley.com], I could use this material to form the edges of the triangular panels, but how would I form the connectors at the corners? If I have to transition to another material to make the joint (one of the photos in the article showed an aluminum end-cap), how much strength do I lose?

      For that matter, how does this material help me create stronger panels for my dome? Could you form a sandwich with it, sort of like the aluminum honeycomb material used in Formula One race cars [ohio-state.edu]?

      Chip H.
  • There are many materials lighter and
    stronger than steel. If that were the
    only important criteria, all modern
    structures would be made of carbon
    fiber. Since structures are big, and
    require lots of material, the most
    important question is: how much does
    it cost?

  • This is not even slightly new or revolutionary (Score:3, Informative)

    by p4k ( 317034 ) on Monday June 03, 2002 @02:21PM (#3633137)
    Will everyone saying how cool this is *please* read the article properly, not just look at the pictures.

    They are *not* claiming to have a new material, their "product" is simply a triangulated braced beam made of carbon or glass fibre. Woohoo, a well designed braced beam made of carbon fibre is lighter than a solid block of steel, well that's a major advance for engineering. NOT. The only slightly unusual feature is that the bracing extends beyond the longitudinal members, but if that significantly improved strength/weight ratio, everyone would be doing it already. In fact, some quick back-of-the-envelope work suggests that its a fair bit worse.

    Structures made of carbon/glass composites are way to expensive to make to be any use in buildings (production is very labour-intensive), and I see nothing on their website to suggest they have successfully addressed this.

    My guess is their business plan depends on either getting bought by someone clueless, or abusing the patent system to get royalties from general engineering companies. On that subject, I would really like to know what exactly they think is worthy of a patent? The angle of the bracing?

  • Just what we need for space elevator :p Uh huh, right.

  • not as strong as its made out to be (Score:3, Insightful)

    by littlerubberfeet ( 453565 ) on Monday June 03, 2002 @04:32PM (#3634274)
    I rock climb. I use carabiners, specifically blackdiamond Locking D's with asymetrical gates. These are rated at 22 KiloNewtons. Some quick calculations: A newton = .2248 pounds. So: .2248* 1000(kilo)*22 newtons = 4946 pounds. Which is two tonnes approx. Ergo, 2 of my climbing 'biners can support two tonnes. Each carabiner weighs less than one half of a pound.
    www.convert-me.com was my resource.
    Am I not getting something here? It all seems wrong to me.

  • Not What it's cracked up to be. (Score:4, Informative)

    by katarn ( 110199 ) on Monday June 03, 2002 @05:27PM (#3634653)

    Okay, to summarize:

    1. There is nothing new about Carbon Fiber. The supposedly 'original' thing here is NOT the material, it's the structural design.
    2. People have been using triangles in structural designs for over 100 years. This looks like a cool demonstration of what some basic engineering principles can do with modern materials, but nothing truly new or patentable. This may make an interesting collage course, but the rest of the hype seems to be just B.S.
    3. Yes, some of the pictures are poorly faked, but they are at least labeled as such.
    4. Since this is nothing new, these material/ structure will have all the problems inherent with any carbon fiber structure. They will be prone to invisible stress fractures, breaking before bending, and be $$. Don't get me wrong, carbon fiber is great for some application. But it's generally best for applications where constant inspection and knowledgeable care can be continually provided. High performance hang gliders are made from carbon fiber. Personally my hang glider is good old aluminum. Much less $$$ and more forgiving of stupidity for us beginners. And a telephone pole, a power pole, or a street sign does not receive anywhere near the maintenance, inspection, and care as even a beginner's hang glider.
    5. If you want to see something truly NEW done with carbon fiber, check this out. [subarustore.com] I must admit *I* would have never thought to make this item out of carbon fiber. And, incidently, I think THIS is where these folks should put their patents.
    • The claimed new part is that the fibers are running through and around the joints of a 3 dimensional structure. It has been done with sheets of triangles. It has been done with bulk materials like steel. The claim is that it hasn't been done before with 3D meshes of fibers which are then cast in resin.

      The weight savings is significant where most of the weight being supported is the weight of the support structure itself. Thus the importance for windmills and communication towers.

      We won't see this stuff in use until someone figures out how to make it at a reasonable price.

  • This is pretty cool stuff. Even cooler that it was made at a university by students and faculty.
  • This thing lacks a few details:

    -How is this stronger defined ?
    When e.g. bending concourns most plastic are stronger than steel. What do we speak about here push/pull, impact, breaking or what ?

    -So its also less heavier than steel
    big deal a lot of things are leighter than steel (so is kevlar, ever seen a kevlar bridge?), it really depens on what this material can be used for and what heats in can withstand, manufactoring cost etc. Its 10% the weight if the other factors are contrary to those of steel it maybe nice but will never be impleted in products.

    The whole website is just a bit too slick, without any real details.

  • This'll make it easier for the neighborhood kids to climb to the top and electrocute themselves. I smell a lawsuit.

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