| Pretty hard to make wires out of ceramics (yes, it's ceramics, not plastic). I heard the Japanese managed to make wires, although I have no clue how. This stuff behaves like typical ceramics, i.e., you kick it, it breaks - and it's impossible to bend. The high-Tc 160K (Tc=-110C max) superconductors still require liquid nitrogen (77K, not 4K like liquid Helium). That's a lot cheaper than Helium, but still seems far from any commercial application. I'm afraid, superconductivity requires another (5-th) Nobel physics prize contribution to make anything commercially useful. You need Tc=500-600 K (300C), for superconductors to work safely without powerful refrigerators. But if discovered, THAT will make a true revolution in technology comparable to invention of electricity. There is no physical limit on the transition temperature, but it looks that the particular cuprate compounds have reached their limit of Tc. (160K). Now, this January a completely new class of high-Tc superconductors was discovered, with a structure of graphite (MgB2) and Tc=40K (the first superconductor of the "cuprate" class also had this temperature), so there is hope :) |
