Preparation and characterization of non-random YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7</inf>-Ag composite

Silver addition to the high T c superconductor, YBa2Cu3O7 (YBCO) is known to improve its mechanical properties and critical current (J c) characteristics. We have synthesized the superconductor-metal composite YBCO-Ag by an electroless process at room temperature (using sucrose or hydrazine hydrate in an alkaline medium). The latter method produces a non-random coating whereby each grain of YBCO is coated uniformly by silver. The intrinsic high T c of 90 K of YBCO can be recovered by compaction of the composite and subsequent heat treatment (900°C and 600°C) in oxygen. © 1992 Indian Academy of Sciences.