ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
(Bi,Pb)2Sr2Ca2Cu3O10 (Bi2223) precursor powders with large and small amounts of Ca2PbO4 phase were prepared and used to make superconductor/silver composite tapes. The melting behavior of the powders and tapes was examined by differential thermal analysis (DTA). The influence of Ca2PbO4 on the formation and microstructure of Bi2223, and electrical properties of the tapes, was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and critical current measurements. It was found that the melting onset temperature (Tm,onset) of precursor powders and composite tapes was strongly dependent on the amount of Ca2PbO4. Tapes with a small amount of Ca2PbO4 had a higher Tm,onset and a higher optimum sintering temperature compared with tapes with a large amount of Ca2PbO4. Also because of the higher sintering temperature, the total sintering time required for the former tapes was drastically shortened compared with the latter ones (250 vs 110 h). Furthermore, the microstructure and the current-carrying capacity of the tapes were significantly improved by reducing the Ca2PbO4 content of the precursor powders. These results are of practical significance for the commercialization of Bi-based high-temperature superconductors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.2000.tb01448.x
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