Critical Current in High-J $ _{rm c}$ Nb $_{3}$Sn Rutherford Cables Affected Substantially by the Direction of the Applied Magnetic Field

摘要

Recently several Rutherford-type ${hbox{Nb}}_{3}{hbox{Sn}}$ cables for possible use in new magnets for upgrades of the LHC have been measured at CERN. A summary is provided including a comparison of the critical current $(I_{c})$ of various cable types and strand materials versus their respective extracted strand measurements. The conductors were cabled at CERN and Lawrence Berkeley National Laboratory. The summary shows an unsurprising linear relation between the strand and the cable performance. However, assuming that the local peak magnetic field in the conductor is the relevant factor for determining the $I_{c}(B)$ relation, a discrepancy is found when results from different directions of applied magnetic field on the cable are compared.