HIPped High Density Bi-(Pb)-Sr-Ca-Cu-O Superconductors Produced without Any Additional Treatment

Abstract

Superconducting ceramics (BiSrCaCu 2 O x and BiPb y SrCaCu 2 O x ) were directly obtained for the first time by a hot isostatic press (HIP) densification without any additional treatment. The ceramics obtained from BiSrCaCu 2 O x were 85 K superconductors and the ones obtained from BiPb y SrCaCu 2 O x had a high- T c phase, which was not observed before the HIP process. The HIPped BiSrCaCu 2 O x samples were densified to 5600 kg/m 3 , and with PbO additions, the density was around 6000 kg/m 3 . All the conventionally processed samples had a lower T c,zero of 65 K and lower densities of about 4600 kg/m 3 . A remarkable improvement in crystallinity and sharper superconducting transition were achieved through the HIP densification process without any additional treatment.