Size reduction of Nd 4Ba 2Cu 2O 10 second phase particles in NdBa 2Cu 3O 7 − y melt-textured at reduced oxygen partial pressure

Abstract

Melt-textured NdBa 2Cu 3O 7 − y (Nd123) superconductor containing fine Nd 4Ba 2Cu 2O 10 (Nd422) particles was prepared by using Nd 1.8Ba 2.4Cu 3.4O x (Nd1.8) powder attrition-milled with 1 wt% CeO 2 addition. The effect of the CeO 2 addition on the size reduction of the Nd422 was remarkable and similar as those observed for Y 2BaCuO 5 (Y211)/Sm 2BaCuO 5 (Sm211) in the Y-Ba-Cu-O/Sm-Ba-CuO system. The Nd422 particles were finely dispersed within the melt-textured Nd123 matrix with a narrow size distribution of a few microns. Superconducting transition temperatures ( T c) of the Nd123 and the Nd1.8 samples melt-textured in an oxygen partial pressure of P( O 2) = 0.001 atm were as high as 95 K.