Critical currents of superconducting BiPbSrCaCuO tapes in the magnetic flux density range 0–19.75 T at 4.2, 15, and 20 K

Abstract

Critical currents of superconducting silver-sheathed tapes of Bi1.8Pb0.4Sr2Ca2.2Cu3Ox have been measured in the magnetic flux density range 0–19.75 T at 4.2, 15, and 20 K. One tape achieved a critical current of 60.6 A at 19.75 T and 20 K; the corresponding critical current density is 551 A/mm2. In the same field, the tape has critical currents of 72.3 A (657 A/mm2) at 15 K and 94.2 A (856 A/mm2) at 4.2 K. At 77 K and in zero field, the tape carries 32.9 A (299 A/mm2). These results indicate that ‘‘high Tc’’ superconducting magnets of engineering interest may soon be feasible.