ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Ag-sheathed Bi2Sr2Ca1Cu2Ox(Bi-2212) tapes with various oxide superconductor core (SC-core) thicknesses, SC-core ratios (SC-core area to overall cross-sectional area), and tape configurations were prepared by a partial melting and slow cooling process. For single-core tapes the critical current density, Jc(core), for SC-core, increases with decreasing SC-core thickness, due to the highly aligned Bi-2212 grains, and the highest Jc(core) of 1.4×105 A/cm2 at 4.2 K in 10 T is achieved at a core thickness of 15 μm. Furthermore, the Jc(core) increases with increasing SC-core ratio (i.e., with decreasing Ag-sheath thickness). From the practical point of view, high Jc(overall) as well as high critical current (Ic) is more important than Jc(core). This requirement is attained by the double-tube method, which shows the highest Jc(overall) value of 3.0×104 A/cm2 at 4.2 K in 10 T. In the tape fabrication process, the slow heating rate just below the partial melting becomes important, because oxygen released from the SC-core during heating makes void swelling in the Ag sheath and leads to the degradation of Jc.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.109449
Permalink