Quench Degradation Limits and Mechanisms of High Current Density Ag/Bi-2223Superconducting Tapes
Session Number
R13
Advisor(s)
Tengming Shen, Fermi National Accelerator Laboratory
Location
B-133
Start Date
28-4-2016 9:50 AM
End Date
28-4-2016 10:15 AM
Abstract
Quench degradation properties are important issues in understanding the stability of high-temperature superconductors (HTS). With a growing interest in Ag-alloy- sheathed BiSr2Ca2Cu3O8+x (Bi2223) as an implementable HTS for commercial applications in high-field magnets, it is crucial that its quench behavior and degradation limits, including conditions that decrease its critical current, are well understood. However, there still is a knowledge gap for Ag/Bi2223 tapes. This investigation aims to experimentally determine quench degradation behaviors and the temperature limit that can be used to develop an effective quench protection system. Short samples of control-overpressure processed (CTOP), high current density Bi2223 from Sumitomo were quenched with a local heater at 77 Kelvin. Under varied quenching conditions, the voltage and temperature changes were recorded and analyzed to identify any correlation. Preliminary results suggest that the Bi2223 samples showed a highly significant sensitivity to temperature during quenching, exhibiting irreversible decreases in critical current at < 200 sensitivity to temperature during quenching, exhibiting irreversible decreases in critical current at < 200 Kelvin.
Quench Degradation Limits and Mechanisms of High Current Density Ag/Bi-2223Superconducting Tapes
B-133
Quench degradation properties are important issues in understanding the stability of high-temperature superconductors (HTS). With a growing interest in Ag-alloy- sheathed BiSr2Ca2Cu3O8+x (Bi2223) as an implementable HTS for commercial applications in high-field magnets, it is crucial that its quench behavior and degradation limits, including conditions that decrease its critical current, are well understood. However, there still is a knowledge gap for Ag/Bi2223 tapes. This investigation aims to experimentally determine quench degradation behaviors and the temperature limit that can be used to develop an effective quench protection system. Short samples of control-overpressure processed (CTOP), high current density Bi2223 from Sumitomo were quenched with a local heater at 77 Kelvin. Under varied quenching conditions, the voltage and temperature changes were recorded and analyzed to identify any correlation. Preliminary results suggest that the Bi2223 samples showed a highly significant sensitivity to temperature during quenching, exhibiting irreversible decreases in critical current at < 200 sensitivity to temperature during quenching, exhibiting irreversible decreases in critical current at < 200 Kelvin.