2010 R&D 100 Winner
Superconducting wire could be to electric power transmission what fiber-optics has been to communications; but superconducting wire is still too costly to manufacture. Los Alamos National Laboratory, Los Alamos, N.M., has developed its Solution Deposition Planarization (SDP) in an effort to reduce these production costs and support much higher power densities. In order to be able to carry high electrical current, the crystalline structure of the superconductor must be highly aligned.
SDP is used in conjunction with ion-beam assisted deposition (IBAD), which won an R&D 100 Award in 2003. In IBAD, a single-crystal-like oxide template is applied to the metal substrate, then a superconducting layer is then deposited epitaxially on the thin 5-nm IBAD layer. This thinness requires a smooth surface, which is provided through SDP by dip-coating the substrate in a liquid precursor mixture of yttrium acetate and alcohol. The coated metal tape is baked at 500°C, which evaporates the alcohol and converts the yttrium acetate into yttrium oxide. As it dries, the coating shrinks, following the original substrate contours. Repeated dipping and baking creates an increasingly smoother surface.
This process eliminates strong acids associated with electroplating alternatives, and the elimination of defects results in higher power densities. More importantly, SDP opens the door to the use of better substrates with improved corrosion resistance, magnetic properties, or tensile strength.
Technology
Dip-coating process for superconducting wires
Developers
Los Alamos National Laboratory
Sandia National Laboratories
Development Team
The Solution Deposition Planarization (SDP) Superconductor Substrate Preparation Process Development Team:
Paul Clem, Sandia National Laboratories
Cynthia Edney, Sandia National Laboratories
Terry Holesinger, Los Alamos National Laboratory
John F. Ihlefeld, Sandia National Laboratories
Vladimir Matias, Los Alamos National Laboratory
Chris Sheehan, Los Alamos National Laboratory
