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A Building Material 12 Times Stronger Than Steel
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 .
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?
In Murphy We Turst
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.
>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.
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.