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The effect of hot pressing conditions (sintering temperature and time) on the superconducting properties of (2223) Bi(Pb)SrCaCuO were investigated by transport and magnetic measurements. The advancement of the densification process leads first to an improvement of the electrical connectivity between grains (Jc transport increases) and then to a deterioration of both intragranular and intergranular properties (Tc, Jc magnetic and Jc transportdecrease) because of the induced loss of oxygen, 2212 continuous intergrain network and other defect formation. [ABSTRACT FROM AUTHOR]

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)/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-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 dc magnetic measurements. The (Nd,Sm)123 samples, appear comparable to Y123 grown with a pulling rate almost two orders of magnitude lower. [ABSTRACT FROM PUBLISHER]