JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM, cilt.24, sa.5, ss.1577-1584, 2011 (SCI-Expanded)
In this study, four kinds of melt-processed YBCO samples were fabricated with the MPMG procedure. The compacted powders were located on a crucible with a buffer layer of Y2O3 to avoid liquid to spread on the furnace plate. Their microstructures were defined by XRD analysis and polarized light optical microscopy. The microstructure investigations indicated that the 123 grains were very big and fine and dispersed 211 particles remained in the samples. Resistivities of the samples were measured by a standard continuous dc four-probe method. Magnetization measurements were made and flux jumps were observed at a relatively higher temperature for Y1060. The critical current density, J (c) , values of the samples, measured by VSM in 5 T magnetic field, exceeded 0.6x10(3) Aa <...cm(-2) at 77 K and 4 T.