Directional solidification of bulk (Y, Sm, Nd)(1)Ba2Cu3O7-x

Rare Earth (Nd, Sm) elements, having relatively large ionic radius, have been substituted for Yttrium in Y123 superconducting melt textured bulk samples. In (Nd, Sm)123 a wider solidification range and higher recrystallization rate than Y123 significantly increase the solidification rate, making the whole process much faster. A preliminary comparison among directionally solidified (Y, Sm, Nd)(1)Ba2Cu3O7-x bulk bars fabricated by the Horizontal Bridgman method has been done. The different microstructural and superconducting features are studied by X-ray, SEM analysis, and ac and de magnetic measurements. The (Nd, Sm)123 samples, appear comparable to Y123 grown with a pulling rate almost two orders of magnitude lower.