Overpressure processing of Ag-sheathed Bi-2212 tapes
نویسندگان
چکیده
منابع مشابه
Bi - 2212 r Ag tapes melt - grown under an elevated magnetic field ž / 0 – 10 T
Bi-2212rAg tapes with a thickness of 30 mm were melt-grown in elevated magnetic fields following two different thermal sequences. The transport critical current density, J dependence on the maximum processing temperature, cooling c rate, holding time and magnetic field was studied systematically. The quantity of impurity phase was decreased by reducing the holding time above the melting point o...
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It is well known that longer Bi-2212 conductors have significantly lower critical current density (Jc) than shorter ones, and recently it has become clear that a major cause of this reduction is internal gas pressure generated during heat treatment, which expands the wire diameter and dedensifies the Bi-2212 filaments. Here we report on the length-dependent expansion of 5 to 240 cm lengths of s...
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We examined the distribution of vortices in both Bi-2223 Ag-sheathed tape and U-doped Bi-2223 Ag-sheathed tape applying the high-resolution Bitter method. In the low temperature region ( ), we found that the vortices in the undoped Bi-2223 Ag-sheathed tape developed into either a triangular arrangement or a heterogeneous arrangement along the grain boundaries of the Ag sheath, which form weak p...
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Ag/Bi-2223 tapes were fabricated using the Powder-In-Tube method, involyH1~ intermediate deformation techniques of sandwich rolling (SR), pressing (P) and nQl1l1~~ rolling (NR). Magnetic field B depen:lence of Jc was measured. Depending 6rt:~~' relationship between )c and B, the irreversible magnetic field Birr was determineli)lIl..W: pinning force density F was calculated. The experimental res...
متن کاملRole of internal gases and creep of Ag in controlling the critical current density of Ag-sheathed Bi2Sr2CaCu2Ox wires
High engineering critical current density JE of > 500A/mm 2 at 20T and 4.2K can be regularly achieved in Ag-sheathed multifilamentary Bi2Sr2CaCu2Ox (Bi-2212) round wire when the sample length is several centimeters. However, JE(20T) in Bi-2212 wires of several meters length, as well as longer pieces wound in coils, rarely exceeds 200A/mm. Moreover, long-length wires often exhibit signs of Bi-22...
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ژورنال
عنوان ژورنال: IEEE Transactions on Appiled Superconductivity
سال: 1997
ISSN: 1051-8223
DOI: 10.1109/77.620867