Preparation of Multi-Core Bi-2212/Ag Wires

Abstract:

The core breaking mechanism of the traditional Bi-2212 wires with filament configuration of 85×7 during the drawing process was analyzed, and the solution of these problems was given. The results showed that the major reason of core breaking occurs was that the tensile stress was bigger on the center than the edge of Bi-2212 wires during the drawing, and the silver-superconductor ratio was smaller of the center than the edge of the traditional Bi-2212 wires. It was effective to avoid the core breaking of Bi-2212 wires using the Ag core strengthener, and the uniformity of distortion of Bi-2212 wires during the drawing was improved, and the critical current of Bi-2212 wires increased 40% than that of traditional wires. If the diameter of the filament of Bi-2212 wires decreased further, there would be lots of bridging between core and core, which provided routeway for current. So the critical current of Bi-2212 wires was improved further.

• Periodical: Materials Science Forum (Volumes 745-746)
• Pages: 168-172
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.745-746.168
• Online since: February 2013
• Authors: Qing Bin Hao, Cheng Shan Li, Sheng Nan Zhang, Gao Shan Li, Li Feng Bai, Guo Qing Liu, Ping Xiang Zhang
• Keywords: Bi-2212 Wire, Drawing, Filament Configuration

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