GRAIN-BOUNDARY COMPOSITIONS IN STOICHIOMETRIC AND OFF-STOICHIOMETRIC Y1BA2CU3O7-X

被引：17

作者：

ALEXANDER, KB ^{[1
]}

KROEGER, DM ^{[1
]}

BENTLEY, J ^{[1
]}

BRYNESTAD, J ^{[1
]}

机构：

[1] OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831

来源：

PHYSICA C | 1991年 / 180卷 / 5-6期

关键词：

D O I：

10.1016/0921-4534(91)90545-A

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The grain boundary segregation behavior of stoichiometric and off-stoichiometric YBa2Cu3O7-x has been studied with analytical electron microscopy (AEM) to complement previous results obtained with Auger electron spectroscopy (AES). It was observed that the grain boundary segregation levels varied from boundary to boundary. In stoichiometry material, excess copper and deficient oxygen were observed at the grain boundaries. In materials containing excess barium, excess yttrium and deficient copper levels were observed at the grain boundaries. The grain boundary segregation levels in the materials containing excess barium can be related to the resistivity and critical current density results. Preferential segregation to specific sites in grain boundaries was observed by AEM. The effect of grain boundary segregation on the superconducting properties of these materials is discussed in terms of the weak link behavior and a possible percolative mechanism in order to maintain a continuous current path.

引用

页码：337 / 350

页数：14

共 45 条

[1]

ALEXANDER KB, 1990, SPR MAT RES SOC M

[2] THE EFFECT OF DENSITY ON CRITICAL CURRENT AND OXYGEN STOICHIOMETRY OF YBA2CU3OX SUPERCONDUCTORS [J].