Correlation between the formation of growth bands and Nd210 addition in Nd/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// bulk samples

1 cm diameter single domain NdBaCuO pellets, obtained from powders of Nd/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// (Nd123) with Nd/sub 2/BaO/sub 4/ (Nd210) addition, have been successfully prepared by top seeding melt textured growth technique. Distribution of Nd/sub 4/Ba/sub 2/Cu/sub 2/O/sub 10/ (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.