Hot isostatically pressed Bi-Sr-Ca-Cu-O

The Bi 2 Sr 2 CaCu 2 O X phase was synthesized by the solid state reaction of oxides and carbonates. Powders with 2.5 and 5 wt.% metallic Ag additions were also synthesized. The powders were cold pressed into pellets, which were hot isostatically pressed at a pressure of 105 MPa in an argon atmosphere at 850 degrees C. The resultant pellets were fully dense. No decomposition of the Bi 2 Sr 2 CaCu 2 O X phase was apparent. Ag was present primarily at grain boundaries. Annealing in 1% oxygen/99% argon at 600 degrees C raised T c from 76 K for the as-isostatically-pressed specimens to 83 K.