Magnetization Measurements of CORCTMand Roebel Type YBCO Cables for Accelerators Using a ±3-T Dipole Magnetometer

We present measurements on high-temperature superconducting (HTS) superconducting cables using a NbTi-wound, 3-T dipole ac magnetometer. Our goal is to measure the magnetization properties of the cables for use in accelerator magnet field error calculations. YBCO-wound CORCTM and Roebel cables were measured in pool boiling helium with no epoxy impregnation. The Roebel cable was a 9–5.6 style, while the CORCTM sample had 16 tapes, and was 3.21 mm OD. For measurement, the samples were inserted in a G-10 holder with pickup and compensation coils, and subjected to a ramping dipole field. The signals were read from a set of nanovoltmeters using data aquisition (DAQ) to monitor the pickup coils, and the data were imported into a LabVIEW software program. The Roebel and CORCTM cable measurements were compared to one another and to the tapes they were made with. Maximum cable magnetization was 1000 kA/m for the CORC and 2200 kA/m for the Roebel when normalizing to total cable volume. These values increased to 2860 and 2640 kA/m, respectively, when normalizing to tape volume.