28 June 2015 to 2 July 2015
JW Marriott Starr Pass Resort
Etc/GMT-7 timezone

Effect of heat treatment and test barrel materials on critical current measurements of Ag/Bi2212 round wires using ITER barrel configurations

1 Jul 2015, 09:00
2h
Exhibit Hall (Arizona Ballroom) ()

Exhibit Hall (Arizona Ballroom)

Poster Presentation ICMC-03 - BSCCO Processing and Properties M3PoA - Superconductor Materials IV: Properties and Applications

Speaker

Tengming Shen (Fermilab)

Description

Critical current measurement for Ag/Bi-2212 wires has been typically performed by mounting a short sample (4-10 cm long) heat treated standalone at ~830 °C on a room temperature G-10 sample holder and cooling them down to cryogenic temperatures. During this process samples experience a huge temperature and strain change. This strain effect has not been carefully considered for critical current measurement, despite that critical current of Ag/Bi-2212 wires is well known to depend on strain. At Fermilab and BNL we began to use a new protocol by reacting meter long samples on 96% pure Al2O3 ITER barrels and transferring them to test barrels made from Ti-6Al-4V alloy. We are extending the study to include tests on barrels made from 304 stainless steel, Inconel 600, and G-10. Samples that will be investigated include wires heat-treated using 1 bar partial melt processing and an overpressure partial melt processing. Initial measurements showed that samples tested on the G-10 barrel reproduce Ic for short witness samples, while the Ti-alloy barrel results in a 10% Ic reduction. Fitting these Ic measurement results into the Ic-strain curves from previous research, the thermal pre-strain for the samples measured on the Ti-alloy, Stainless Steel, and G-10 will be evaluated. *This work is supported by the U.S. Department of Energy, Office of High Energy Physics through a FY12 early career award.*

Primary author

Liyang Ye (Fermi National Accelerator Laboratory)

Co-authors

Arup Ghosh (Brookhaven National Laboratory) Pei Li (Fermi National Accelerator Laboratory) Tengming Shen (Fermilab)

Presentation Materials