The study for improvement of critical current density Jc using Nb/Al multilayer films was carried out. In order to resolve the role of the two stage heat treatment, which was very effective for powder metallurgy processed Nb3Al wires, samples deposited on quartz substrates were heat-treated under various conditions and examined by X-ray analyses. Superconducting properties were measured and compared with those of powder process. In multilayer films prepared with a nominal layer thickness ratio Nb/Al=3/1 which corresponds to 26.5 at.% Al, a thick Nb layer of 900 Å was needed to show high Jc properties. These results were much different from data reported by Bormann et al. on the 25 at.% Al multilayers.
ASJC Scopus subject areas
- Physics and Astronomy(all)