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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Temperature Dependence of the Intergranular Critical Current Density in Uniaxially Pressed Bi1.65Pb0.35Sr2Ca2Cu3O10+delta Samples

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Autor(es):
Garcia-Fornaris, I. [1] ; Planas, A. A. [1] ; Mune, P. [2] ; Jardim, R. F. [3] ; Govea-Alcaide, E. [2]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Univ Granma, Dept Ciencias Basicas, Bayamo - Cuba
[2] Univ Oriente, Dept Fis, Santiago De Cuba - Cuba
[3] Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo - Brazil
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Journal of Superconductivity and Novel Magnetism; v. 23, n. 8, p. 1511-1516, DEC 2010.
Citações Web of Science: 5
Resumo

We have studied the normal and superconducting transport properties of Bi(1.65)Pb(0.35)Sr(2)Ca(2)Cu(3)O(10+delta) (Bi-2223) ceramic samples. Four samples, from the same batch, were prepared by the solid-state reaction method and pressed uniaxially at different compacting pressures, ranging from 90 to 250 MPa before the last heat treatment. From the temperature dependence of the electrical resistivity, combined with current conduction models for cuprates, we were able to separate contributions arising from both the grain misalignment and microstructural defects. The behavior of the critical current density as a function of temperature at zero applied magnetic field, J (c) (T), was fitted to the relationship J (c) (T)ae(1-T/T (c) ) (n) , with na parts per thousand 2 in all samples. We have also investigated the behavior of the product J (c) rho (sr) , where rho (sr) is the specific resistance of the grain-boundary. The results were interpreted by considering the relation between these parameters and the grain-boundary angle, theta, with increasing the uniaxial compacting pressure. We have found that the above type of mechanical deformation improves the alignment of the grains. Consequently the samples exhibit an enhance in the intergranular properties, resulting in a decrease of the specific resistance of the grain-boundary and an increase in the critical current density. (AU)

Processo FAPESP: 09/51562-3 - Ernesto Govea Alcaide | Universidad de Oriente - Cuba
Beneficiário:Renato de Figueiredo Jardim
Linha de fomento: Auxílio à Pesquisa - Pesquisador Visitante - Internacional
Processo FAPESP: 05/53241-9 - Estudo de fenômenos intergranulares em materiais cerâmicos
Beneficiário:Reginaldo Muccillo
Linha de fomento: Auxílio à Pesquisa - Temático