DYBA2CU3O7-Y SUPERCONDUCTING MATERIALS SYNTHESIZED IN-SITU IN A MAGNETIC-FIELD - RELATIONS BETWEEN STRUCTURE AND PROPERTIES

We have synthesized c-axis oriented magnetically melt textured grown D yBa2Cu3O7-y samples at 1035 degrees C under a 0.6T magnetic induction. We discuss the crystal growth mechanism of such 123 melt textured gro wn superconducting ceramics. A strictly tridimensional model is propos ed based on Schmitz et al. model, taking into account the peculiar phy sical properties reported for such materials. In particular a filament ary one dimensional electron conduction path at the percolation thresh old is emphasized. We have used optically polarized light microscopy a s well as electron microscopy analysis to deduce the growth steps.