For state-of-the-art superconductors, NIST investigates the mechanical behavior of RABiTS. (General Developments).One of the major challenges facing the development of an economical, practical, high-temperature superconductor A material that has little resistance to the flow of electricity. Traditional superconductors operate at absolute zero (-459.67 degrees Fahrenheit or -273.15 degrees Celsius). Experiments in the 1980s raised the temperature to -321 degrees Fahrenheit. has been the extremely weak mechanical behavior of Y-Ba-Cu-O coated onto rolling-aligned biaxially textured substrates (RABiTS). The RABiTS process is of great interest because it has the potential to be easily scalable to fabricate industrial quantities of this promising superconductor. In the past several months, a private company has produced a new RABiTS coated conductor with substrates made of nickel plus 0.05 mass fraction tungsten tungsten (tŭng`stən) [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.85; m.p. about 3,410°C;; b.p. 5,660°C;; sp. gr. 19.3 at 20°C;; valence +2, +3, +4, +5, or +6. . NIST (National Institute of Standards & Technology, Washington, DC, www.nist.gov) The standards-defining agency of the U.S. government, formerly the National Bureau of Standards. It is one of three agencies that fall under the Technology Administration (www.technology. scientists have completed a series of experiments using their specialized equipment for both transverse To cross from side to side. stress and transport current to measure the electromechanical The use of electricity to run moving parts. Disk drives, printers and motors are examples. Electromechanical systems must be designed for the eventual deterioration of moving components that wear over time. The first TVs were electromechanical systems (see video/TV history). performance of this new coated superconductor. The results are striking. The NIST data show that in repeated testing the critical current (the maximum current the conductor can carry) is degraded de·grad·ed adj. 1. Reduced in rank, dignity, or esteem. 2. Having been corrupted or depraved. 3. Having been reduced in quality or value. by only 1 % to 5 % at the benchmark 100 MPa stress level. This result is one of the keys for opening the path for commercialization of RABiTS coated conductors. Projections are that this conductor could be manufactured at about $10 per kiloamperemeter. This cost would be competitive with copper in transformers and in other electric utility applications, and far less expensive than copper for increasing the capacity of underground transmission lines in urban areas. Until now, the RABiTS process had worked only with soft, pure nickel substrates. Earlier NIST measurements showed that the critical current with nickel substrates degraded by as much as 28 % at the benchmark 100 MPa stress level, which made it unacceptable for use as a practical conductor in many applications. NIST's electromechanical test capability for superconductors is one of the few test facilities of its kind in the world, and the only one providing specialized measurements for United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. superconductor manufacturers. CONTACT: Jack Ekin, (303) 497-5448; ekin@boulder.nist.gov. |
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