POWDER MELTING PROCESS FOR YBA2CU3O7-Y SUPERCONDUCTOR BY EUTECTIC FORMATION

dYBa(2)Cu(3)O(7-y) with high grain alignment has been successfully fab ricated by a modified powder melting process at a temperature of simil ar to 930 degrees C, which is near the eutectic point of the starting materials Y2BaCuO5, BaCuO2, and CuO. In terms of the levitation force and YBa2Cu3O7-y, grain alignment, the best result was shown in a sampl e having a Y2BaCuO5:BaCuO2:CuO molecular ratio of 1:3:5. In the presen t work, the Cu-surplus eutectic liquid was completely absorbed by use of a Y2BaCuO5 substrate, by which the final composition was driven to stoichiometric YBa2Cu3O7-y The results were comparable to those obtain ed by the conventional melt-texture-growth process. A new invariant po int apparently occurred at similar to 930-940 degrees C owing to an in terfacial reaction between YBa2Cu3O7-y matrix and Y2BaCuO5 substrate.