Correlation Between the Formation of Growth Bands and Nd210 Addition in Nd1Ba2Cu3O7-? Bulk Samples

1 cm diameter single domain NdBaCuO pellets, obtained from powders of Nd1Ba2Cu3O7-? (Nd123) with Nd2BaO4 (Nd210) addition, have been successfully prepared by top seeding melt textured growth technique. Distribution of Nd4Ba2Cu2O10 (Nd422) precipitates in the Nd123 matrix has been analyzed by means of polarized light optical microscopy and scanning electron microscopy. Relevant distribution inhomogeneity in the peripheral region of pellets with a high Nd210 addition have been revealed, as well as in regions of dendritic growth and around pores. Increasing difficulties in obtaining a complete growth of the single domain samples, in dependence of increasing Nd210 addition has been observed too. A qualitative growth model for high Nd concentration samples has been proposed to explain both these behaviors.