Imaging of Current Sharing in (BiPb)_2Sr_2Ca_2Cu_3Ox Composite Conductors.
Abstract
Using a high-resolution magneto-optical imaging technique, we study the flow of transport currents around cracks in mono-filament (BiPb)_2Sr_2Ca_2Cu_3Ox composite conductors. Shunting through the Ag clad is directly observed. The current in the silver decays exponentially with distance from the crack (as expected in a one dimentional resistor model). At 77K, the decay length, λ, is approximately 0.04 cm, implying an interface resistivity of 1.5 10-7Ωcm^2. This decay length is found to increase with increasing temperature. For crack densities higher than 26/cm, a portion of the current resides in the clad. ^This work is supported by the U.S. DOE, BES-Materials Science (TBP,UW,GWC) and EERE (NV,JPS,MTL) under contract #W-31-109-ENG-38, and the Russian foundation of Fundamental Studies Grant Potok(VKV,VIN) ^Permanent Address: Institute for Solid State Physics, 142432 Chernogolovka, Moscow district, Russia
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR..M903P