DIRECTIONAL SOLIDIFICATION OF BULK (Y, SM, ND)(1)BA2CU3O7-X

Rare Earth (Nd, Sm) elements, having relatively large ionic radius, ha ve been substituted for Yttrium in Y123 superconducting melt textured bulk samples. In (Nd, Sm)123 a wider solidification range and higher r ecrystallization rate than Y123 significantly increase the solidificat ion rate, making the whole process much faster. A preliminary comparis on among directionally solidified (Y, Sm, Nd)(1)Ba2Cu3O7-x bulk bars f abricated by the Horizontal Bridgman method has been done. The differe nt microstructural and superconducting features are studied by X-ray, SEM analysis, and ac and de magnetic measurements. The (Nd, Sm)123 sam ples, appear comparable to Y123 grown with a pulling rate almost two o rders of magnitude lower.