Abstract
Extremely fine normal-conducting particles could be uniformly dispersed in the superconductive matrix through a combination of Pt addition and a mixture of three different LRE (LRE: `light rare earths', i.e. Nd, Eu, Gd) elements in the LRE-Ba2Cu3Oy system. Although (Nd,Eu,Gd)2BaCuO5 powders about 3 μm in diameter were added to the precursor, we have found that Gd2BaCuO5 (Gd-211) inclusions about 0.1 μm in diameter were finely distributed in the (Nd,Eu,Gd)Ba2Cu3Oy matrix. The formation of such fine normal-conducting particles has not been achieved in any other bulk superconductors like YBa2Cu3O7 or NdBa2Cu3O7. The presence of small Gd-211 did not inhibit the function of flux pinning provided by composition fluctuations leading to a spatial scatter of the superconducting transition temperature, Tc, which is typically observed in LRE-Ba2Cu3Oy materials, which have a LRE1-xBa2-xCU3Oy-type solid solution. Therefore, two different pinning centers are simultaneously active in one sample, which is also confirmed by the pinning analysis based on the scaling formalism, and leading to a record high current density for bulk high temperature superconductors at 77 K.
Original language | English |
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Pages (from-to) | 58-65 |
Number of pages | 8 |
Journal | Materials Science and Engineering B: Solid-State Materials for Advanced Technology |
Volume | 65 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1999 Oct 29 |
Externally published | Yes |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering