This is an excerpt from EERE Network News, a weekly electronic newsletter.
Advances in Materials Show New Promise for Superconductors
It was bound to happen: "superconductor"—a material able to carry electrical current with little or no resistance—has long been one of those technology buzzwords you could impress your friends with, but in recent years it has been largely supplanted by the latest thing, "nanotechnology," the use of materials at the sub-microscopic scale of a billionth of a meter, or nanometer. So leave it to a superconductor company to put the two together! American Superconductor Corporation is currently selling 10-meter lengths of its second-generation high-temperature superconductor (HTS) wire to select customers, but plans to enhance the product by dispersing "nanodots"—particles of inorganic materials—throughout the superconductor coating in the wire. The technical explanation is that the nanodots immobilize magnetic lines of flux in the superconductor, but the bottom line is that they allow 30 percent more current to flow through the wire. The company expects to produce the second-generation HTS wire in commercial volumes in three to four years. See the American Superconductor press release.
DOE's national laboratories are also advancing superconductor technology. At DOE's Los Alamos National Laboratory, researchers have found a way to produce superconductor wire from magnesium diboride, a material that was found to be a superconductor in early 2001. Although the material is much cheaper than earlier superconductors, researchers have had difficulty fabricating useful products from it. The Los Alamos researchers overcame that difficulty by subjecting the material to high pressures and temperatures, a process known as hot isostatic pressing. They were able to produce 80 feet of wire that was able to carry 45 percent more current than previous magnesium diboride wires. See the Los Alamos press release.
DOE's Brookhaven National Laboratory (BNL) is investigating yet another class of superconductors, made from cobalt oxide. A BNL scientist has found a way to make the superconductor, sodium cobalt oxyhydrate, without using dangerous chemicals. The superconductor is unusual because the compound contains water; if allowed to dry out it loses its superconductivity. See the BNL press release.