High Temperature Superconducting Composites With Low Alternating Current Loss

40518 American Superconductor Corporation Many applications of high temperature superconductors (HTS) involve conductor performance in time-varying magnetic fields. Such environments require very stringent AC loss requirements for a commercially viable product. Available parameters for AC loss mitigation in composite conductors include filament dimension, conductor matrix dimension, matrix resistivity perpendicular to the magnetic field, and current density. While many AC applications are already feasible with typical Bi-2223 filament dimensions, the effective transverse resistivity between filaments must be very high, much higher than most known metals or metal alloys compatible with HTS materials. This project will develop a processing concept that greatly increases the effective transverse resistivity and simultaneously reduces the effective conductor matrix dimension for AC loss, without sacrificing the proven benefits of fine Ag stabilizer adjacent to Bi-2223 filaments. Phase I will develop the necessary processing parameters for creating the desired composite morphology. Phase II will develop a robust, competitive commercial process for HTS AC conductor. Anticipated Results/Potential Commercial Applications as described by the awardee: Application spin-offs of this effort extend to any HTS application performing in time varying magnetic fields, including transformers, power electronics, SMES, and fast ramping magnets.