AC loss in cored, stabrite-coated, superconducting cables in response to external compaction and variation of core thickness and width

AC loss due to coupling currents in a Rutherford cable can be modified by changing the interstrand contact resistance (ICR) by: adjusting the level of native oxidation of the strand, coating it, or by inserting a ribbon-like core into the cable itself. With regard to cored cables further effective-ICR adjustments can be achieved by changing: (i) the degree of compaction during manufacture, (ii) the thickness of the core at fixed overall thickness, and (iii) the width of the core. We report on the results of magnetic and calorimetric AC loss measurements on stainless-steel-cored stabrite cables which had been: (i) externally compacted by rolling to thicknesses of 0%, 6%, 9%, and 11% below the standard thickness, (ii) internally compacted by being furnished with cores of thicknesses 1 mil (25 μm) and 2 mil (50 μm), and (ii) furnished with cores whose widths, wcore, were about 20%, 50%, 75% and 100% of the maximum available width. The measurements were made in applied AC fields that were directed perpendicular (face-on, FO) and parallel (edge-on, EO), respectively, to the broad cables faces.