AG-DOPED 120-K YBA2CU3O7-DELTA SUPERCONDUCTORS PREPARED BY THE FLAME-QUENCH-MELT-GROWTH (FQMG) METHOD

The effect of Ag-doping on the microstructure and physical properties of YBa2Cu3O7-delta superconductors prepared by a flame-quench-melt-gro wth (FQMG) process, was investigated. Pellets of YBa2Cu3O7-delta conta ining 0-30 weight percentage (wt.%) of Ag were quenched by LPG-O-2 fla me melting and then crushed to obtain powder which was compacted and t hen subjected to a melt-growth process. As a result of this process, l arge grained, textured YBCO material was produced. It was found that Y BCO samples with 10 wt.% Ag doped showed a transition temperature of 1 20 K and further increasing the Ag content caused a decrease of transi tion temperature. Using this modified quench-melt-growth technique, th e reaction between crucibles and material can be completely avoided du ring the preparation of the precursor materials.