Effects of hot-rolling on powder-in-tube BSCCO tapes

Conference · Thu Jul 01 04:00:00 EDT 1993

OSTI ID:10179087

Guo, J; Schwartz, J ^[1]; Cha, Y S; Wu, C T; Goretta, K C ^[2]

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1. Univ. of Illinois, Urbana, IL (US). Dept of Nuclear Engineering
2. Argonne National Lab., IL (US)

High critical currents have been obtained in Bi-Sr-Ca-Cu-O by the powder-in-tube approach. Owing to the inherent structural anisotropy of the Bi-based high-Tc superconducting materials, high-Jc is only obtained when the wires are subsequently rolled into rectangularly cross-sectioned tapes. Previously, intermediate annealing was employed to maintain ductility in the silver with a high temperature sintering just before the final rolling in order to form the high-Tc superconducting phase. Here, the authors report on the effects of hot-rolling at various temperatures for the final rolling of powder-in-tube BSCCO-2212 tapes. Hot-rolling was accomplished by preheating the rolls with infrared heaters and rolling the tapes directly from the furnace. The highest current densities were obtained by final hot-rolling the 2212 tapes at 420{degrees}C with the furnace temperature of 750{degrees}C, the highest temperature studied. Results showed the enhancement of Jc was due to the improvement of grain alignment as well as the reduction of the size and fraction of Bi-free phases during the final heat treatment. Furthermore, an analytical model of the hot-rolling process has been developed that illustrates the importance of preheating the tapes and heating the rolls.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 10179087
• Report Number(s): ANL/ET/CP--78580; CONF-930703--18; ON: DE93018579
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201
360207
BISMUTH OXIDES
CALCIUM OXIDES
COPPER OXIDES
CRITICAL CURRENT
FABRICATION
HIGH-TC SUPERCONDUCTORS
HOT WORKING
POWDER METALLURGY
ROLLING
SILVER
STRONTIUM OXIDES
SUPERCONDUCTING WIRES
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K