SBIR-STTR Award

Recently, Bi2212 wires fabricated with high quality Bi2212 powders have achieved short-term champion engineering critical current density Je ~1.9 kA/mm2 at 4.2 K and 5 T. However, such superior performance does not pass on to the superconducting coils due to the strong sensitivity of Je on Tmax. A ~37.0 cm long racetrack coil shows less than 70% Je of the corresponding high performance Bi2212 wires1. This makes a great challenge for high field magnet applications, especially for large size accelerator magnets. The superconducting community has identified an urgent need to broad the Tmax window >10 ?C for 75% retention Je so as to fully utilize the high performance of Bi2212 wires. nGimat, teamed with Bruker OST, will demonstrate the feasibility to broaden Tmax window of high-quality Bi2Sr2CaCu2O8+? (Bi2212) powder using its proven NanoSpray Combustion process. In this proposal, we describe a detailed plan to widen the Tmax window of Bi2212 powder with high performance Je for corresponding wires above 1.0 kA/mm2 at 4.2 K and 20 T.

The production of advanced magnets, which are capable of generating magnetic fields of 16 Tesla and higher, requires advances in superconducting conductors that can be produced in volume and that is capable of operating at high temperatures.This program is focused on the development of highperformance bismuth strontium calcium copper oxide powder, or Bi2212, which is a leading candidate material for use in the production of high-temperature superconductor wires.During Phase I, Bi2212 powder was developed with newly-devised processing parameters that allowed the resulting powder to be successfully heat treated in a broader temperature window.This broader temperature window supports the manufacturability of the powder and the resulting wire, positioning it for broader adoption in the superconducting community.Multifilamentary round wire made with Bi2212 can enable advanced performance for high energy physics accelerator magnet applications.During Phase II, further optimization of processing parameters for Bi2212 powder will be performed.The impact of critical powder specifications, including dopants and particle size, will be explored, further enabling the performance boundary of Bi2212 powder and the resulting wire to be expanded.Highperforming powder will be repeatably produced in a scaled-up manner that demonstrates the production capability necessary to support the growing demands in this field.Commercial applications include next-generation systems for nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).Fusion energy and various forms of renewable energy are also potential beneficiaries.