American Superconductor Corporation, a leading electricity solutions company, announced today that it has successfully developed and filed a patent application for a nanotechnology-based manufacturing technique that delivers an immediate 30% increase in the electric current-carrying capability of the company's second generation (2G) high temperature superconductor (HTS) wire.
This new nanotechnology process leverages AMSC's proprietary metal-organic chemical processing methodology by producing a dispersion of "nanodots" throughout the superconductor coating of the company's 2G HTS wire. Nanodots are ultra-small particles of inorganic materials typically less than 100 atoms across. AMSC's 2G HTS wire is being designed as a form-fit-function replacement for today's commercial first generation (1G) HTS wire, but at two to five times lower manufacturing cost, which is expected to further expand the market for HTS applications.
"We have been selling 2G HTS wire in up to 10-meter lengths to select customers around the world and over the next few months we expect to incorporate nanodots into this wire," said Dave Paratore, senior vice president and general manager of AMSC Wires. "The 2G pilot manufacturing plant that we plan to start building at the end of this year will be based upon our nine years of 2G wire research and development. Introducing nanotechnology capabilities into this manufacturing process will help ensure our continued global leadership position in HTS wire."
Paratore added that AMSC remains on track with its plan to produce 2G HTS wire in commercial volumes in three to four years. Nanodots significantly increase the flow of electrical current through 2G HTS wire by immobilizing magnetic lines of flux in the superconductor.
"Based on related laboratory-scale, proof-of-concept work carried out by our research colleagues at the Air Force Research Laboratory and Los Alamos National Laboratory, it is quite clear that by optimizing the size, dispersion and composition of nanodots we can expect to at least double the electrical current flow in 2G wire at the operating temperatures and magnetic fields associated with commercial superconductor applications," said Alex Malozemoff, chief technical officer at American Superconductor.
AMSC is also using another nanotechnology technique in its 2G HTS wire production - a nanotech surface treatment - first developed at Oak Ridge National Laboratory and then transferred through a cooperative research agreement to AMSC. The nanotech surface treatment, which creates a self-assembled superlattice of sulfur atoms, helps ensure very high quality buffer layers on the metal alloy surfaces that provide the foundation for AMSC's 2G HTS wires.
"We have taken Oak Ridge's nanotech surface treatment from the lab to the next level - using it to create buffer layers in a reproducible, reel-to-reel, wire production process," said Malozemoff. "We have repeatedly made 10 metre lengths of 2G wire utilizing this surface treatment and are now ready to take this particular processing step to the pilot manufacturing stage."