SIZE-REDUCTION OF ND4BA2CU2O10 2ND-PHASE PARTICLES IN NDBA2CU3O7-Y MELT-TEXTURED AT REDUCED OXYGEN PARTIAL-PRESSURE

Melt-textured NdBa2Cu3O7-y (Nd123) superconductor containing fine Nd4B a2Cu2O10 (Nd422) particles was prepared by using Nd1.8Ba2.4Cu3.4Ox (Nd 1.8) powder attrition-milled with 1 wt% CeO2 addition. The effect of t he CeO2 addition on the size reduction of the Nd422 was remarkable and similar as those observed for Y2BaCuO5 (Y211)/Sm2BaCuO5 (Sm211) in th e Y-Ba-Cu-O/Sm-Ba-Cu-O system. The Nd422 particles were finely dispers ed within the melt-textured Nd123 matrix with a narrow size distributi on of a few microns. Superconducting transition temperatures (T-c) of the Nd123 and the Nd1.8 samples melt-textured in an oxygen partial pre ssure of P(O-2)=0.001 atm were as high as 95 K.