Meter Length YBCO Coated Conductor Development--American Superconductor Cor-poration, Two Technology Drive, Westborough, MA 01581; 508-836-4200
Dr. Cornelius L. H. Thieme, Principal Investigator
Dr. Tom Rosa, Business Official
DOE Grant No. DE-FG02-99ER82740
Amount: $750,000

Devices such as power transmission cables, motors and generators can be made very compact when run under cryogenic conditions. For further enhancements in power densities it is highly desirable to use High Temperature Superconductors with a greatly enhanced critical current density (J_c at 50-77K and magnetic fields of up to 3T) which would allow the operation at much higher temperatures. Production cost of these superconductors needs to be substantially reduced to increase their commercial appeal. The Yba₂Cu₃O_x(YBCO) coated conductor offers satisfactory performance at high magnetic fields and high temperatures at a greatly reduced cost. This project will produce long lengths of very tiny, non-magnetic substrates with excellent control over substrate dimensions and texture quality, which will be used to manufacture 20m long YBCO coated conductor with overall critical current densities of 40,000 A/cm² at 77K. The Phase I project resulted in the development and production of thin, well texture non-magnetic foils. Full buffer stacks (ceria/YSZ/ceria) were successfully deposited, with excellent texture. Solution-based YBCO was successfully deposited and reacted on buffered Ni substrates with high critical currents. The Phase II project will produce long lengths of thin, non magnetic substrates with excellent control over substrate dimensions and texture quality, which will be used to manufacture 20m long YBCO Coated Conductors, with overall critical current densities of 40,000 A/cm² at 77K, self field, and 15,000 A/cm² at 50K and 3T.

Commercial Applications and Other Benefits as described by the awardee: The commercial applications of these new YBCO coated conductors are in power transmission cables, motors, generators, transformers, and in magnets for energy storage, magnetic separation, and current limiters. Typically these applications are now addressed by Bi-2223 superconductors. The superior performance of YBCO coated conductor will enable many of these applications to run at higher temperatures and its lower production cost will greatly increase their commercial appeal.