Speaker
Description
Transverse resistance among adjacent conductors is a key parameter to
calculate AC losses in superconducting cables with non-insulated
conductors. The transverse pressure insert (TPI) previously developed
and used at Fermilab was modified to measure transverse resistance of
stacks made of non-insulated REBCO tapes as a function of transverse
pressure at liquid nitrogen temperature. Pressure up to 322 MPa was
applied with a hydraulic cylinder. A small current up to 10 A was flown
in the stack sample through REBCO tape leads spliced above and below the
stack. The latter had a bending radius larger than 6 mm to prevent the
critical current degradation in REBCO leads. The voltage was measured
just outside the compressed area. Stack samples included stacks of bare
4-mm wide REBCO tapes, as well as REBCO tapes alternated with 4-mm wide
stainless-steel ribbons of 40 um and 30 um of thickness. We herein
present the results of these transverse resistance measurements.
Results show a stronger dependence on pressure for smaller pressure vs.
larger ones. Also, of the two components of transverse resistance, i.e.
contact and bulk, the latter was negligible.
