One of my favourite sites is
Stickmaker's Joy of High Tech - lots of interesting essays. However I'm curious about the following section from the
strength of materials page:
Perfect diamond is a another real material, but there is a theoretical material which is far stronger. It, too, uses carbon, but in the form of benzine-like rings. These are looped through each other in a three-dimensional matrix, and the impressive figures (1.0 X 10^15 (that's a 1 followed by 15 zeroes), 9.3 X 10^14, and 9.3 X 10^12 N/cm^2) for the yield strengths come from the fact that not only is deformation resisted by the normal molecular bonds, but by the mutual repulsion of the shared electron clouds around the rings. As you can imagine, this also makes the material extremely rigid. And hard. (My thanks to Dr. John Brantley for telling me about this.)
This sounds really impressive, but I've done various web searches for it over the last few years and I have yet to locate a corroborating source. I searched this board just now, but the closest thread I could find was
this one, which doesn't cover this. Similarly:
As mentioned above, perfect iron has been made and tested in the laboratory... in laboratory quantities. Whiskers (to the materials engineer, a whisker is a fibre with no imperfections) generally are made by assembling atoms into a perfect matrix in a liquid or vapor phase deposition process. Now that I've explained my units, I can report that the figures for perfect iron are 4,600,000, 4,600,000, and 660,000 in Newtons per square centimeter for tension, compression and shear, respectively. The values for a typical mild steel, such as is normally used for structures, are 46,300, 46,300, and 38600. An excellent commercial steel would have typical values of 463,400, 463,400 and 380,000.
...sounds very impressive, but I'm aware that there's a lot more to a useful material than just these values. Previous threads here appear to have dismissed monocrystalline iron as a practical material (due to brittleness?). Perhaps one of the materials scientists around here could confirm which bits of that page are correct, and if the 'ring carbon composite' material is a real possibility (presumably it would need advanced nanotech to synthesise)? You may also find the
armour essay interesting/worthy of comment.
