High temperature XRD on silver sheathed Bi(Pb)-2223 tapes in different oxygen partial pressures

A detailed study of the phase formation mechanisms of different Bi(Pb)(2)Sr2Ca2Cu3Ox precursors in silver sheathed tapes is presented. The method of high temperature x-ray diffraction was used in different oxygen partial pressures and at various heating rates. Fast formation of Pb3Bi0.5Sr2.5Ca1.5Cu0.5Ox (3321) was observed. At the same temperature where Pb3Bi0.5Sr2.5Ca1.5Cu0.5Ox disappeared, Bi(Pb)(2)Sr2CaCu2Ox started to form crystals. This observation leads to the assumption that the Pb3Bi0.5Sr2.5Ca1.5Cu0.5Ox decomposition is one important factor for the Bi(Pb)(2)Sr2CaCu2Ox growth and, hence, for the Bi(Pb)(2)Sr2Ca2Cu3Ox phase formation.