Phase I Final Technical Report
Two subscale coils of Bi-2212 wire have been made and tested in a DOE 2018 STTR collaboration between Cryomagnetics and the Applied Superconductivity Center at Florida State University. These coils are used to test the feasibility of using small-diameter wire in a solenoidal configuration where single strand wire performance is crucial. If successful, the implementation of small-diameter wire into high field Bi-2212 HTS solenoids will allow for high J_E operation with moderate currents, making feasible the use of more modest control equipment, power supplies, and current leads. Furthermore, lower operating currents may allow series-connected design configurations with LTS background magnets, allowing for better, simpler, and more effective quench protection methods. A 25-Tesla magnet design, consisting of an 8-Tesla Bi-2212 coil with a 17-Tesla LTS coil, is fully underway at Cryomagnetics, and considerations of critical current, hoop stress, and quench protection will all be fully addressed. This document reports our findings up to this point, the end of the Phase I period.