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POSTER CONTRIBUTIONS
Processing and Characterization of Melt-textured Y 1-x Pr x Ba 2 Cu 3 O 7-δ
and [YBa 2 Cu 3 O 7-d ] 1-x [PrBa 2 Cu 3 O 7-d ] x Superconductor
Yuri Aparecido Opata, Lincoln Brum Leite Gusmão Pinheiro, Joao Frederico Haas Leandro
Monteiro, Simone Aparecida Silva, Pedro Rodrigues Jr., Alcione Roberto Jurelo
Department of Physics, Universidade Estadual de Ponta Grossa,Campus Uvaranas - Av.
General Carlos Cavalcanti, 4748 - CEP 84030-900, Campus Central - Praça Santos Andrade,
Ponta Grossa – Paraná, Brazil
e-mail: yuriopata@gmail.com
We report the processing and characterization of top-seeded melt-textured (TSMT) Y1-
xPrxBa2Cu3O7-δ (YPr-123) and [YBa2Cu3O7-d]1-x[PrBa2Cu3O7-d]x (Y/Pr-123), for
x = 0.00 and 0.05. These stoichiometries were chosen for the analysis of the Pr doping
effect on the mechanical properties and critical phenomena. First, we prepared
Nd1.8Ba2.4Cu3.4Oy seeds using NdBa2Cu3Ox and Nd4Ba2Cu2Ox powders. These
two phases were sintered twice at 900 and 1100 °C for 24 h, respectively, and mixed to
have the composition Nd1.8Ba2.4Cu3.4Ox. The seeds precursors were pressed in
pellets, heated at 1136 °C in 2 h and held for 3 h, then rapidly cooled to 1096 °C in 6
min, and slowly cooled to 950 °C in a rate of 1 °C/h. After, we prepared Y1-
xPrxBa2Cu3O7-δ phase, which was calcined in 880, 900 and 920 °C, respectively. The
Y2BaCuO5 (Y-211) and YPr-123 phases were grinded and mixed in proportion 75 %
wt. YPr-123 + 25 % wt. Y-211 + 1 % wt. CeO and pressed in pellets. These samples
were sintered in 920° C for 24 h, heated the 1045° C for 3 h, quickly cooled at 1005 °C
and slowly cooled at 990 °C in 30 h. For the Y/Pr-123 we prepared theYBa2Cu3O7-δ
(Y-123) and PrBa2Cu3O7-δ (Pr-123) phases, these were calcined with the same
temperatures used in the Y/Pr-123. The compounds were mixed in the proportion 75 %
wt. [95 % wt. Y-123 + 5 % wt. Pr-123] + 25 % wt. Y-211 + 1 % wt. CeO. The
successful top-seeded melttextured samples were characterized by X-ray diffraction,
optical microscopy, scanning electron microscopy, resistivity measurements and
mechanical properties by instrumented indentation and conventional Vickers
measurements. To identify power-law divergences of the conductivity, the resistivity
data were analyzed in terms of the temperature derivative of the resistivity and of the
logarithmic temperature derivative of the conductivity.
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