Variable-temperature critical-current measurements on a Nb-Ti wire
Loren F. Goodrich, Theodore C. Stauffer
We made variable-temperature critical-current (Ic) measurements on a commercial multifilamentary Nb-Ti wire for temperatures (T) from 4 to 9 K and magnetic fields (H) from 0 to 11.5 T using transport current. The measurements cover the whole range of critical currents from less than 0.1 A to over 800 A. This sample will be useful as a variable-temperature reference wire. To verify the measurements at variable- temperature, we compared critical currents up to 600 A on a specimen that was immersed in liquid helium to those on the same specimen in flowing helium gas. This comparison indicated our ability to control and measure specimen temperature was within 35 mK. We also calibrated the magnetoresistance effect of resistive thermometers for temperatures from 4 to 35 K and magnetic fields from 0 to 12 T. The critical-current data presented include electric field-current (E-I) characteristics, and E-T characteristics at constant I and H,Ic(H) at constant T, and Ic(T) at constant H.
Advances in Cryogenic Engineering
September 23-26, 2003
Anchorage, AK, USA
International Cryogenic Materials Conference (ICMC)
critical current, high current, n-value, Nb-Ti, superconductor, temperature margin, thermometry, variable temperature