Influence of strand surface condition on interstrand contact resistance and coupling loss in NbTi-wound Rutherford cables

Presented in this work are the results of directly measured and AC-loss-der ived interstrand contact resistance (ICR) measurements performed magnetical ly or resistively on bare-Cu and coated-strand pairs, calorimetrically on I i-strand Rutherford cables wound with strands that had been coated with var ious metallic and insulating layers, and calorimetrically and magnetically on 28-strand Rutherford cables (LHC-type) wound with bare-Cu-, Ni-, and sta brite-plated strands. Comparisons are made of the effects of various condit ions of heat treatment, HT (time and temperature), and pressure (applied du ring HT and then either maintained or re-applied during measurement). The r esulting ICRs are compared and interpreted in terms of the oxide layer on t he strand coating and its response to curing conditions. (C) 1999 Elsevier Science Ltd. All rights reserved.